An Apple Peel a Day Could Keep Cancer at Bay
An apple peel a day might help keep cancer at bay, according to Rui Hai Liu, Cornell associate professor of food science, who has identified a dozen compounds -- triterpenoids -- in apple peel that either inhibit or kill cancer cells in laboratory cultures. Three of the compounds have not previously been described in the literature.
"We found that several compounds have potent anti-proliferative activities against human liver, colon and breast cancer cells and may be partially responsible for the anti-cancer activities of whole apples," says Liu, who is affiliated with Cornell's Institute of Comparative and Environmental Toxicology and is senior author of the study, which is online and published in the Journal of Agricultural and Food Chemistry.
In previous Cornell studies, apples had been found not only to fight cancer cells in the laboratory but also to reduce the number and size of mammary tumors in rats. The Cornell researchers now think that the triterpenoids may be doing much of the anti-cancer work.
"Some compounds were more potent and acted differently against the various cancer cell lines, but they all show very potent anti-cancer activities and should be studied further," says Liu.
With co-author Xiangjiu He, a Cornell postdoctoral researcher, Liu analyzed the peel from 230 pounds of red delicious apples from the Cornell Orchard and isolated their individual compounds. After identifying the structures of the promising compounds in the peel, the researchers tested the pure compounds against cancer cell growth in the laboratory. In the past, Liu has also identified compounds called phytochemicals -- mainly flavonoids and phenolic acids -- in apples and other foods that appear to be have anti-cancer properties as well, including inhibiting tumor growth in human breast cancer cells.
"We believe that a recommendation that consumers to eat five to 12 servings of a wide variety of fruits and vegetables daily is appropriate to reduce the risks of chronic diseases, including cancer, and to meet nutrient requirements for optimum health," said Liu.
The study online: http://pubs.acs.org/cgi-bin/abstract.cgi/jafcau/2007/55/i11/abs/jf063563o.html
Adults who eat apples, drink apple juice have lower risk for metabolic syndrome
Apple product consumers likely to have lower blood pressure, trimmer waistlines, and more nutrient dense diets
Not eating your apple a day" Perhaps you should be. Adults who eat apples, apple juice and applesauce have a significantly reduced risk of metabolic syndrome, a cluster of health problems that are linked to numerous chronic diseases such as diabetes and cardiovascular disease.
The study results, presented at the Experimental Biology 2008 meeting this week, were derived from an analysis of adult food consumption data collected in the 1999-2004 National Health and Nutrition Examination Survey (NHANES), the government’s largest food consumption and health database.
Dr. Victor Fulgoni analyzed the data, specifically looking at the association between consumption of apples and apple products, nutrient intake and various physiological parameters related to metabolic syndrome. When compared to non-consumers, adult apple product consumers had a 27% decreased likelihood of being diagnosed with metabolic syndrome.
Fulgoni notes, “We found that adults who eat apples and apple products have smaller waistlines that indicate less abdominal fat, lower blood pressure and a reduced risk for developing what is known as the metabolic syndrome.”
In addition to having a 30% decreased likelihood for elevated diastolic blood pressure and a 36% decreased likelihood for elevated systolic blood pressure, apple product consumers also had a 21% reduced risk of increased waist circumference – all predictors of cardiovascular disease and an increased likelihood of metabolic syndrome. Additionally, adult apple product consumers had significantly reduced C-reactive protein levels, another measurable marker related to cardiovascular risk.
Furthermore, apple product consumers’ diets were healthier than non-consumers – they had an overall greater intake of fruit and key nutrients, including dietary fiber, vitamins A and C, calcium and potassium. These consumers also ate less total fat, saturated fat, discretionary fat and added sugars.
Apple pectin, apple juice extracts shown to have anticarcinogenic effects on colon
The apples and apple juice you consume may have positive effects in one of the most unlikely places in the body – in the colon. New research has demonstrated that both apple pectin and polyphenol-rich apple juice components actually enhance biological mechanisms that produce anticarcinogenic compounds during the fermentation process.
Using human fecal matter as the test substance, German researchers Dr. Dieter Schrenk, M.D. and his colleagues hypothesized that the compound butyrate could be increased in the presence of apple pectin and apple juice extracts.
Butyrate has been suggested to be a chemopreventative metabolite that might prevent the occurrence of colorectal cancer, which is very common in Western industrialized countries. It is a short chain fatty acid which is seen as a major factor contributing to healthy colon mucosa. The research notes, “Butyrate not only serves as a major nutrient for the colon epithelia but is also thought to play an important role in the protective effect of natural fiber against colorectal cancer.”
So how do apple pectin and apple juice extracts play a role in increasing amounts of butyrate? The laboratory tests performed by Schrenk found that by the increased production of butyrate via the addition of apple components, histone deacetlyases (HDAC) were inhibited. With slowed production of HDAC, there would be significantly less growth of precancerous and tumor cells.
The research, published in the April 2008 issue of Nutrition, notes, “apples are a major source of natural fiber and of low molecular weight plan polyphenols in the Western diet.” The researchers conclude, “Pectin-rich apple products can thus be expected to exert anticarginogenic effects in the colon.”
Apple consumers reap heart-health benefits
Apples may prove to be a winner when it comes to reducing the risk of heart disease, says a new study of more than 34,000 women. In this study, flavonoid-rich apples were found to be one of three foods (along with red wine and pears) that decrease the risk of mortality for both coronary heart disease (CHD) and cardiovascular disease (CVD) among post-menopausal women, The findings were published in the March 2007 American Journal of Clinical Nutrition.__
Women of all ages are encouraged to consume more fruit and vegetables, including apples and apple products, for heart health. However, this study focused on postmenopausal woman, a group becoming more aware of the risk for heart disease. Using a government database that assesses the flavonoid-compound content of foods, the researchers hypothesized that flavonoid intake (in general and from specific foods), might be inversely associated with mortality from CVD and CHD among the women in the study groupSubjects selected for this research analysis were postmenopausal and part of the ongoing Iowa Women's Health Study, each of which has been monitored for dietary intake and various health outcomes for nearly 20 years._
As a result of the extensive analysis that considered what the women ate, the types of cardiovascular-related diseases they experienced, and the overall flavonoid content of an extensive list of foods, the researchers concluded that consumption of apples, pears and red wine were linked with the lowest risk for mortality related to both CHD and CVD (not just one or the other).
"Flavonoids are compounds found in small quantities in numerous plant foods, including fruits and vegetables, tea, wine, nuts and seeds, and herbs and spices," say the university researchers from the University of Minnesota and the University of Oslo (Norway) Earlier research has indicated that flavonoids also have antioxidant properties that are linked to the reduction of oxidation of the bad (LDL - low density lipoprotein) cholesterol which have been linked in various ways with the development of CVD. According to the government database cited in this paper, apples contain a wide variety of flavonoid compounds.__
The researchers also believe this is the first prospective study of postmenopausal women to report on the intake and impact of total and specific flavonoid subclasses. They conclude, "Dietary intakes of flavanones, anthocyanins, and certain foods rich in flavonoids were associated with reduced risk of death due to CHD, CVD and all causes."__
The publication of this positive study for apples comes on the heels of updated heart disease prevention guidelines for women just released by the American Heart Association in the February 20 issue of Circulation. As part of their guidelines, AHA emphasizes that women increase their intake of fruits and vegetables to help prevent heart disease over their lifetime, not just to reduce short-term risk. Worldwide, cardiovascular disease is the largest single cause of mortality among women, accounting for one third of all deaths.
Can an apple a day keep asthma away?
Poor diets show increased respiratory symptoms in teens
Teenagers who forego a healthy and balanced diet may have a harder time catching their breath. A new study, published in the July issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP), shows that a low dietary intake of certain nutrients increases the likelihood of respiratory symptoms such as asthma, especially in teens who smoke. Furthermore, a lack of these nutrients may also lead to lower lung function.
“Our study, as well as other research, suggests that higher intakes of antioxidant and anti-inflammatory micronutrients are associated with lower reports of cough, respiratory infections, and less severe asthma-related symptoms,” said lead study author Jane Burns, ScD, Harvard School of Public Health. “Teenagers who have low dietary intakes of fruit, vitamin E, and omega-3 fatty acids are at greater risk of having asthma, emphasizing the importance of a balanced diet, composed of whole foods.”
While observing 12th-grade students from 12 communities around the US and Canada, Dr. Burns and her colleagues from the Harvard School of Public Health, Health Canada, Brigham and Women’s Hospital, and the Environmental Protection Agency (EPA), examined the associations of low dietary nutrient intake with low pulmonary function and respiratory symptoms. Over the period of one school year, 2,112 students completed a standardized respiratory questionnaire and a dietary questionnaire. They also answered questions about medication use, smoking habits, and recent exercise, before participating in lung function testing. Dr. Burns explained that the researchers focused on teens because it is the ideal age at which to test lung capacity and eating habits.
“During late adolescence, physical stature has, on average, been attained and lung growth closely parallels this growth. Therefore we were observing a time when lung function was close to its optimal capacity,” she said. “Also, although our diet survey targeted eating habits only during the past year, it did give us some idea of the teens’ general past diet. However, their current respiratory health may be a reflection of diet during childhood, as well as during the past year.”
The majority of adolescents in the study were white, one third was overweight, and 72% did not consume multivitamins. Also, nearly 25% reported smoking on a daily basis. Researchers also found that at least one third of the students’ diets were below the recommended levels of fruit, vegetable, vitamins A and E, beta-carotene, and omega-3 fatty acid intake.
“Vitamin supplements can help teens meet their daily recommended levels,” said Dr. Burns, “and surprisingly, even relatively low levels of omega-3 fatty acids appeared to protect teens from higher reported respiratory symptoms.”
Results showed that low dietary intakes of fruit, vitamins C and E, and omega-3 fatty acids were associated with decreased lung function and a greater risk of chronic bronchitic symptoms, wheeze, and asthma. These risks were further increased among students with the lowest intakes and who also smoked.
“I wish we could say that an apple a day can keep asthma away, but it’s a complex disease with a genetic component. However, it may be that certain foods can lessen or prevent asthma symptoms,” said Dr. Burns. “The most important thing to remember is that diet can have a significant impact on teens’ respiratory health. I would encourage them to make healthy eating a part of their daily routine, and stress to them that smoking is bad.” Researchers emphasized that fresh fruits make for convenient snacks. They also suggest preparing a simple, daily family meal, as a method to promote both communication and good nutrition.
“A balanced diet is not only good for lung health, but for general health,” said Mark J. Rosen, MD, FCCP, President of the American College of Chest Physicians. “Parents and physicians should work together to monitor and maintain healthy diets and lifestyles for children of all ages.”
Apples, apple juice shown to prevent early atherosclerosis
A new study shows that apples and apple juice are playing the same health league as the often-touted purple grapes and grape juice. The study was published in the April 2008 issue of Molecular Nutrition and Food Research.
Researcher Kelly Decorde from the Universite Montpelier in France was part of the European research team that found apples have similar cardiovascular protective properties to grapes. The researchers also observed that processing the fruit into juice has the potential to increase the bioavailability of the naturally-occurring compounds and antioxidants found in the whole fruit.
Using a variety of established analytical techniques, aortic plaque was evaluated to determine the effectiveness in decreasing plaque that is associated with atherosclerosis.
According to the research, “This study demonstrates that processing apples and purple grapes into juice modifies the protective effect of their phenolics against diet induced oxidative stress and early atherosclerosis in hypercholesterolemic hamsters.”
Researchers also noted, “These results show for the first time that long-term consumption of antioxidants supplied by apples and purple grapes, especially phenolic compounds, prevents the development of atherosclerosis in hamsters, and that the processing can have a major impact on the potential health effects of a product.”
In summary, the researchers stated that their work would help provide encouragement that fruit and fruit juices may have significant clinical and public health relevance.
Apples, Apple Juice Lower Wheezing and Asthma Risk in Children
Published in the September 2007 issue of Thorax, the latest study finds that when women ate apples during pregnancy, researchers found a significant decrease in asthma and wheezing among their children when the children were followed over five years and reached five years of age.
This unique longitudinal study tracked dietary intake by 1253 mother-child pairs. According to the researchers that conducted medical evaluations for asthma and related symptoms (i.e., wheezing) in the children, they found no other association with decreased risk other than for apple consumption. The only other positive association found between prenatal food intake and risk reduction in the children was with fish intake by the mothers, for which the researchers found that children of mothers who ate fish had a lowered incidence of doctor-confirmed eczema.
A similar but different study published June 2007 also showed a link between apple juice consumption and a reduction in wheezing among children. That study was published in June’s European Respiratory Journal.
Among children who experienced what was characterized as “current wheeze” (where the child had wheezing or whistling in the chest in the last 12 months), there was a significant, dose response association between consumption of apple juice and a reduced incidence of the wheezing. The researchers found that drinking apple juice made from concentrate and consumption of bananas one or more times a day (compared to drinking apple juice or eating bananas less than once a month) was directly associated with improvement of wheezing occurences.
According to the authors of the Thorax paper, the protective effect from apples is attributable to their powerful phytochemical content, which includes flavonoids, isoflavonoids, and phenolic acids. Apples and apple products combined are the largest source of free phenolics in people’s diet in the US and in Europe.
The American Lung Association states that asthma remains a major public health concern. In 2003, approximately 20 million Americans had asthma and the condition accounted for an estimated 12.8 million lost school days in children. Asthma ranks within the top ten prevalent conditions causing limitation of activity and costs our nation $16.1 billion in health care costs annually.
Apple's benefits reach into the womb to fight asthma
Apple's benefits reach into the womb, found to be protective against childhood asthma__Eating apples while pregnant may give new meaning to an apple a day keeping the doctor away. Compelling new research has concluded that mothers who eat apples during pregnancy may protect their children from developing asthma later in life. The study was published in Thorax online.__This unique longitudinal study tracked dietary intake by nearly 2000 pregnant women, then examined the effects of the maternal diet on airway development in more than 1200 of their children five years later. Among a wide variety of foods consumed and recorded by the pregnant women, the researchers concluded that the children of mothers who ate apples had a significantly reduced risk for the development of asthma and childhood wheezing.__This study focuses on medical evaluations for asthma and related symptoms (i.e., wheezing) when the children were five years old. As a result of the evaluations cited in this research, other than apples, there were no consistent associations found between prenatal consumption of a range of healthful foods and asthma in the 1253 children who were evaluated.__Children of mothers who ate apples during pregnancy were much less likely to exhibit symptoms of asthma (including wheezing), say the researchers who hail from institutions in The Netherlands and Scotland. These same researchers previously reported positive associations between maternal consumption of vitamins A, E, D and zinc with reduced risk of asthma, wheeze and eczema in children.__The only other positive association found between prenatal food intake and risk reduction in the children was with fish, for which the researchers found that children of mothers who ate fish had a lowered incidence of doctor-confirmed eczema.__According to the research, "The present study suggests beneficial associations between maternal apple intake during pregnancy and wheeze and asthma at age five years." They add that their findings "suggest an apple specific effect, possibly because of its phytochemical content, such as flavonoids." The research paper cites other related studies on apples, including those which found that "intake of apples as a significant source of flavonoids and other polyphenols has been beneficially associated with asthma, bronchial hypersensitivity, and lung function in adults."__In 2004, the National Center for Health Statistics reported that nine million U.S. children have been diagnosed with asthma at one point in their lives and four million children suffered from asthma attacks that year. Others suffer from "hidden asthma" – undetected or undiagnosed asthma, according the American Lung Association. The cost of this disease is great – statistics show asthma to be the third-ranking cause of hospitalization among children under 15 and is among the leading causes of school absenteeism.
Eating apples/fish helps vs asthma/allergies
Women who eat apples and fish during pregnancy may reduce the risk of their children developing asthma or allergic disease, suggests a new study presented at the American Thoracic Society 2007 International Conference, on Sunday, May 20.__The SEATON study, conducted at the University of Aberdeen, UK, found that the children of mothers who ate the most apples were less likely to ever have wheezed or have doctor-confirmed asthma at the age of 5 years, compared to children of mothers who had the lowest apple consumption. Children of mothers who ate fish once or more a week were less likely to have had eczema than children of mothers who never ate fish.__The study did not find any protective effect against asthma or allergic diseases from many other foods, including vegetables, fruit juice, citrus or kiwi fruit, whole grain products, fat from dairy products or margarine or other low-fat spreads.__The researchers studied 1212 children born to women who had filled out food questionnaires during their pregnancy. When the children were 5 years old, the mothers filled out a questionnaire about the children’s respiratory symptoms and allergies, as well as a questionnaire about their child’s food consumption.__The children were also given lung function and allergy tests. Previous studies in the same children have found evidence for protective effects of vitamin E and D and zinc during pregnancy in reducing the risk of children’s wheeze and asthma, notes researcher Saskia Willers, M.Sc. of Utrecht University in the Netherlands. If the new results are confirmed, she says, "recommendations on dietary modification during pregnancy may help to prevent childhood asthma and allergy."__Willers concludes that at least until age 5, a mother’s diet during pregnancy might be more influential on a child’s respiratory health than the child’s own diet. She notes that further study of this group of children will be needed to see whether the association with the mothers’ diet declines in older children, and if mothers’ and their childrens’ diets interact in older children.__Willers suggests that the beneficial effect of apples may come from powerful antioxidants called flavonoids, while fish’s protective effect may come from omega-3 fatty acids, which other studies have suggested have a protective effect on the heart and may have a protective effect in asthma. "Other studies have looked at individual nutrients’ effect on asthma in pregnancy, but our study looked at specific foods during pregnancy and the subsequent development of childhood asthma and allergies, which is quite new," Willers says. "Foods contain mixtures of nutrients that may contribute more than the sum of their parts."
Naturally-occurring apple compounds reduce risk of pancreatic cancer
Smokers benefit most from intake of 'hidden' plant nutrients
Eating flavonol-rich foods like apples may help reduce the risk of pancreatic cancer, says a team of international researchers. Quercetin, which is found naturally in apples and onions, has been identified as one of the most beneficial flavonols in preventing and reducing the risk of pancreatic cancer. Although the overall risk was reduced among the study participants, smokers who consumed foods rich in flavonols had a significantly greater risk reduction.
This study, published in the October 15 issue of the American Journal of Epidemiology, is the first of its kind to evaluate the effect of flavonols – compounds found specifically in plants – on developing pancreatic cancer. According to the research paper, “only a few prospective studies have investigated flavonols as risk factors for cancer, none of which has included pancreatic cancer. “
Researchers from Germany, the Univ. of Hawaii and Univ. of Southern California tracked food intake and health outcomes of 183,518 participants in the Multiethnic Cohort Study for eight years. The study evaluated the participants’ food consumption and calculated the intake of the three flavonols quercetin, kaempferol, and myricetin. The analyses determined that flavonol intake does have an impact on the risk for developing pancreatic cancer.
The most significant finding was among smokers. Smokers with the lowest intake of flavonols presented with the most pancreatic cancer. Smoking is an established risk factor for the often fatal pancreatic cancer, notes the research.
Among the other findings were that women had the highest intake of total flavonols and seventy percent of the flavonol intake came from quercetin, linked to apple and onion consumption.
It is believed that these compounds may have anticancer effects due to their ability to reduce oxidative stress and alter other cellular functions related to cancer development.
“Unlike many of the dietary components, flavonols are concentrated in specific foods rather than in broader food groups, for example, in apples rather than in all fruit,” notes the research study. Previously, the most consistent inverse association was found between flavonols, especially quercetin in apples and lung cancer, as pointed out in this study. No other epidemiological flavonol studies have included evaluation of pancreatic cancer.
While found in many plants, flavonols are found in high concentrations in apples, onions, tea, berries, kale, and broccoli. Quercetin is most plentiful in apples and onions.
Friday, December 26, 2008
Tuesday, December 23, 2008
Certain Vegetables Combat Cancer
Women should go for the broccoli when the relish tray comes around during holiday celebrations this season.
While it has been known for some time that eating cruciferous vegetables, such as broccoli, cauliflower, and cabbage, can help prevent breast cancer, the mechanism by which the active substances in these vegetables inhibit cell proliferation was unknown - until now.
Scientists in the UC Santa Barbara laboratories of Leslie Wilson, professor of biochemistry and pharmacology, and Mary Ann Jordan, adjunct professor in the Department of Molecular, Cellular, and Developmental Biology, have shown how the healing power of these vegetables works at the cellular level. Their research is published in this month's journal Carcinogenesis.
"Breast cancer, the second leading cause of cancer deaths in women, can be protected against by eating cruciferous vegetables such as cabbage and near relatives of cabbage such as broccoli and cauliflower," said first author Olga Azarenko, who is a graduate student at UCSB. "These vegetables contain compounds called isothiocyanates which we believe to be responsible for the cancer-preventive and anti-carcinogenic activities in these vegetables. Broccoli and broccoli sprouts have the highest amount of the isothiocyanates.
"Our paper focuses on the anti-cancer activity of one of these compounds, called sulforaphane, or SFN," Azarenko added. "It has already been shown to reduce the incidence and rate of chemically induced mammary tumors in animals. It inhibits the growth of cultured human breast cancer cells, leading to cell death."
Azarenko made the surprising discovery that SFN inhibits the proliferation of human tumor cells by a mechanism similar to the way that the anticancer drugs taxol and vincristine inhibit cell division during mitosis. Mitosis is the process in which the duplicated DNA in the form of chromosomes is accurately distributed to the two daughter cells when a cell divides.
Hundreds of tiny tube-like structures, called microtubules, make up the machinery that cells use to separate the chromosomes. SFN, like the more powerful anticancer agents, interferes with microtubule functioning during mitosis in a similar manner to the more powerful anticancer drugs. However SFN is much weaker than these other plant-based drugs, and thus much less toxic.
"SFN may be an effective cancer preventive agent because it inhibits the proliferation and kills precancerous cells," said Wilson. It is also possible that it could be used as an addition to taxol and other similar drugs to increase effective killing of tumor cells without increased toxicity.
While it has been known for some time that eating cruciferous vegetables, such as broccoli, cauliflower, and cabbage, can help prevent breast cancer, the mechanism by which the active substances in these vegetables inhibit cell proliferation was unknown - until now.
Scientists in the UC Santa Barbara laboratories of Leslie Wilson, professor of biochemistry and pharmacology, and Mary Ann Jordan, adjunct professor in the Department of Molecular, Cellular, and Developmental Biology, have shown how the healing power of these vegetables works at the cellular level. Their research is published in this month's journal Carcinogenesis.
"Breast cancer, the second leading cause of cancer deaths in women, can be protected against by eating cruciferous vegetables such as cabbage and near relatives of cabbage such as broccoli and cauliflower," said first author Olga Azarenko, who is a graduate student at UCSB. "These vegetables contain compounds called isothiocyanates which we believe to be responsible for the cancer-preventive and anti-carcinogenic activities in these vegetables. Broccoli and broccoli sprouts have the highest amount of the isothiocyanates.
"Our paper focuses on the anti-cancer activity of one of these compounds, called sulforaphane, or SFN," Azarenko added. "It has already been shown to reduce the incidence and rate of chemically induced mammary tumors in animals. It inhibits the growth of cultured human breast cancer cells, leading to cell death."
Azarenko made the surprising discovery that SFN inhibits the proliferation of human tumor cells by a mechanism similar to the way that the anticancer drugs taxol and vincristine inhibit cell division during mitosis. Mitosis is the process in which the duplicated DNA in the form of chromosomes is accurately distributed to the two daughter cells when a cell divides.
Hundreds of tiny tube-like structures, called microtubules, make up the machinery that cells use to separate the chromosomes. SFN, like the more powerful anticancer agents, interferes with microtubule functioning during mitosis in a similar manner to the more powerful anticancer drugs. However SFN is much weaker than these other plant-based drugs, and thus much less toxic.
"SFN may be an effective cancer preventive agent because it inhibits the proliferation and kills precancerous cells," said Wilson. It is also possible that it could be used as an addition to taxol and other similar drugs to increase effective killing of tumor cells without increased toxicity.
Friday, December 19, 2008
Jon's Health Tips - Yogurt
I eat non-fat yogurt several times a week as a dessert or snack. Here’s why:
Health Benefits of Yogurt
Yogurt may not be the miracle food some have claimed, but it certainly has a lot to offer in the health department. Besides being an excellent source of bone-building calcium, it is believed that the bacterial cultures Lactobacillus bulgaricus (L. bulgaricus) and Streptococcus thermophilus (S. thermophilus), that are used to make yogurt, carry their own health benefits.
For example, research has suggested that eating yogurt regularly helps boost the body's immune-system function, warding off colds and possibly even helping to fend off cancer. It is also thought the friendly bacteria found in many types of yogurt can help prevent and even remedy diarrhea.
For people who suffer from lactose intolerance, yogurt is often well tolerated because live yogurt cultures produce lactase, making the lactose sugar in the yogurt easier to digest (see Lactose Intolerance for advice on coping with this condition). Be sure to check the label on the yogurt carton for the National Yogurt Association's Live and Active Cultures (LAC) seal. This seal identifies products that contain a significant amount of live and active cultures. But don't look to frozen yogurt as an option; most frozen yogurt contains little of the healthful bacteria.
One research study tracked a population of 162 very elderly people for five years. The incidence of death for those subjects who ate yogurt and milk more than three times per week was 38% lower than the incidence of death those subjects who ate yogurt and other dairy foods less than once a week. (Consuming citrus fruit twice a week and a lowered consumption of meat were also associated with decreased incidence of death).
Yogurt Cuts Bladder Cancer Risk
Intakes of various foods and nutrients could influence the risk of bladder cancer, because most metabolites are excreted through the urinary bladder. With regard to dietary factors, consumption of milk and other dairy foods could potentially reduce the risk of bladder cancer.
This study aimed to examine the association between the intake of cultured milk and other dairy foods and the incidence of bladder cancer.
A statistically significant inverse association was observed for the intake of cultured milk (sour milk and yogurt). The intake of milk or cheese did not affect bladder cancer risk.
Cultured milk products contain lactic acid bacteria, which have been shown to suppress bladder carcinogenesis in rodents. The mechanism accounting for the antitumor effect of lactic acid bacteria is not clear, but it may be related to modulation of the immune system. In addition, oral administration of lactic acid bacteria has been shown to suppress food-derived urinary mutagenicity in humans, thus possibly reducing bladder carcinogenesis. The authors conclude that that a high intake of cultured milk may lower the risk of developing bladder cancer.
Dairy foods protect against many ills
Dairy foods protect against the clustering of abnormal body chemistry known as the metabolic syndrome, suggests a study in the Journal of Epidemiology and Community Health .
The syndrome has been linked to an increased risk of diabetes, coronary artery disease, and premature death.
Two or more out of high blood glucose, insulin, blood fats, body fat, and blood pressure defined the presence of the metabolic syndrome in the men studied.
These men had almost double the risk of coronary artery heart disease and four times the risk of diabetes of those without the syndrome. They were also almost 50% more likely to die early.
But those who regularly drank milk and ate dairy products, such as yogurt and cheese, were significantly less likely to have the syndrome.
They were 62% less likely to have it if they drank a pint or more of milk every day, and 56% less likely to have it if they regularly ate other dairy produce.
And the more dairy produce the men consumed, the less likely were they to have the syndrome.
Study suggests a little milk could go a long way for your heart
New research links drinking lowfat milk to lower risk for heart disease
Grabbing as little as one glass of lowfat or fat free milk could help protect your heart, according to a new study published in the American Journal of Clinical Nutrition. Researchers found that adults who had at least one serving of lowfat milk or milk products each day had 37 percent lower odds of poor kidney function linked to heart disease compared to those who drank little or no lowfat milk.
To determine heart disease risk, researchers from several universities in the United States and Norway measured the kidney function of more than 5,000 older adults ages 45 to 84. They tracked eating patterns and tested albumin-to-creatinine ratio (ACR) – a measure that when too low, can indicate poor kidney function and an extremely high risk for cardiovascular disease, according to the American Heart Association.
Researchers found that people who reported consuming more lowfat milk and milk products had lower ACR, or healthier kidney function. In fact, lowfat milk and milk products was the only food group evaluated that on its own, was significantly linked to a reduced risk for kidney dysfunction. The study authors cited other research suggesting milk protein, vitamin D, magnesium and calcium may contribute to milk's potential heart health benefits.
An overall healthy diet, including lowfat milk and milk products, whole grains, fruits and vegetables was also associated with a benefit – 20 percent lower ACR or healthier kidney function.
The National Kidney Foundation estimates that kidney disease affects about 26 million Americans – and kidney disease is both a cause and a consequence of cardiovascular disease, the number one killer of Americans. An estimated one out of three adults is currently living with some form of cardiovascular disease.
Milk provides nine essential nutrients, including calcium, vitamin A, vitamin D, protein and potassium. The U.S. Dietary Guidelines for Americans recommend drinking three glasses of lowfat or fat free milk each day.
Drinking milk may help ease the pressure
New study suggests fat-free milk may offer protection against hypertension -- a rising risk for women in this country
Women who drank more fat free milk and had higher intakes of calcium and vitamin D from foods, and not supplements, tended to have a lower risk for developing hypertension or high blood pressure, according to a new study published in the American Heart Association journal, Hypertension.
After examining the diets of nearly 30,000 middle-aged and older women, Harvard researchers found that women who consumed more low-fat milk and milk products and had diets higher in calcium and vitamin D from foods were better protected against high blood pressure. When the researchers investigated the benefits of milk specifically, they found women who drank two or more servings of fat free milk each day reduced their risk for high blood pressure by up to10 percent compared to those who drank fat free milk less than once a month. The same was not found for higher fat milk and milk products or calcium and vitamin D supplement users.
One in three American adults has high blood pressure, and an increasing number of women are living with undiagnosed hypertension, according to a second study published in the journal Circulation. The last decade has seen significant increases in uncontrolled high blood pressure for women across the nation, a condition that puts them at serious risk for cardiovascular disease, stroke and even kidney failure.
Yet despite a vast body of research linking diet changes to blood pressure control, most Americans are still missing the mark on their diets. According to new research published in the Archives of Internal Medicine, Americans are ignoring the DASH (Dietary Approaches to Stop Hypertension) Diet, the therapeutic eating plan recommended by the National Heart Lung and Blood Institute that emphasizes low-fat dairy, fruits and vegetables to help reduce blood pressure levels.
Health Benefits of Yogurt
Yogurt may not be the miracle food some have claimed, but it certainly has a lot to offer in the health department. Besides being an excellent source of bone-building calcium, it is believed that the bacterial cultures Lactobacillus bulgaricus (L. bulgaricus) and Streptococcus thermophilus (S. thermophilus), that are used to make yogurt, carry their own health benefits.
For example, research has suggested that eating yogurt regularly helps boost the body's immune-system function, warding off colds and possibly even helping to fend off cancer. It is also thought the friendly bacteria found in many types of yogurt can help prevent and even remedy diarrhea.
For people who suffer from lactose intolerance, yogurt is often well tolerated because live yogurt cultures produce lactase, making the lactose sugar in the yogurt easier to digest (see Lactose Intolerance for advice on coping with this condition). Be sure to check the label on the yogurt carton for the National Yogurt Association's Live and Active Cultures (LAC) seal. This seal identifies products that contain a significant amount of live and active cultures. But don't look to frozen yogurt as an option; most frozen yogurt contains little of the healthful bacteria.
One research study tracked a population of 162 very elderly people for five years. The incidence of death for those subjects who ate yogurt and milk more than three times per week was 38% lower than the incidence of death those subjects who ate yogurt and other dairy foods less than once a week. (Consuming citrus fruit twice a week and a lowered consumption of meat were also associated with decreased incidence of death).
Yogurt Cuts Bladder Cancer Risk
Intakes of various foods and nutrients could influence the risk of bladder cancer, because most metabolites are excreted through the urinary bladder. With regard to dietary factors, consumption of milk and other dairy foods could potentially reduce the risk of bladder cancer.
This study aimed to examine the association between the intake of cultured milk and other dairy foods and the incidence of bladder cancer.
A statistically significant inverse association was observed for the intake of cultured milk (sour milk and yogurt). The intake of milk or cheese did not affect bladder cancer risk.
Cultured milk products contain lactic acid bacteria, which have been shown to suppress bladder carcinogenesis in rodents. The mechanism accounting for the antitumor effect of lactic acid bacteria is not clear, but it may be related to modulation of the immune system. In addition, oral administration of lactic acid bacteria has been shown to suppress food-derived urinary mutagenicity in humans, thus possibly reducing bladder carcinogenesis. The authors conclude that that a high intake of cultured milk may lower the risk of developing bladder cancer.
Dairy foods protect against many ills
Dairy foods protect against the clustering of abnormal body chemistry known as the metabolic syndrome, suggests a study in the Journal of Epidemiology and Community Health .
The syndrome has been linked to an increased risk of diabetes, coronary artery disease, and premature death.
Two or more out of high blood glucose, insulin, blood fats, body fat, and blood pressure defined the presence of the metabolic syndrome in the men studied.
These men had almost double the risk of coronary artery heart disease and four times the risk of diabetes of those without the syndrome. They were also almost 50% more likely to die early.
But those who regularly drank milk and ate dairy products, such as yogurt and cheese, were significantly less likely to have the syndrome.
They were 62% less likely to have it if they drank a pint or more of milk every day, and 56% less likely to have it if they regularly ate other dairy produce.
And the more dairy produce the men consumed, the less likely were they to have the syndrome.
Study suggests a little milk could go a long way for your heart
New research links drinking lowfat milk to lower risk for heart disease
Grabbing as little as one glass of lowfat or fat free milk could help protect your heart, according to a new study published in the American Journal of Clinical Nutrition. Researchers found that adults who had at least one serving of lowfat milk or milk products each day had 37 percent lower odds of poor kidney function linked to heart disease compared to those who drank little or no lowfat milk.
To determine heart disease risk, researchers from several universities in the United States and Norway measured the kidney function of more than 5,000 older adults ages 45 to 84. They tracked eating patterns and tested albumin-to-creatinine ratio (ACR) – a measure that when too low, can indicate poor kidney function and an extremely high risk for cardiovascular disease, according to the American Heart Association.
Researchers found that people who reported consuming more lowfat milk and milk products had lower ACR, or healthier kidney function. In fact, lowfat milk and milk products was the only food group evaluated that on its own, was significantly linked to a reduced risk for kidney dysfunction. The study authors cited other research suggesting milk protein, vitamin D, magnesium and calcium may contribute to milk's potential heart health benefits.
An overall healthy diet, including lowfat milk and milk products, whole grains, fruits and vegetables was also associated with a benefit – 20 percent lower ACR or healthier kidney function.
The National Kidney Foundation estimates that kidney disease affects about 26 million Americans – and kidney disease is both a cause and a consequence of cardiovascular disease, the number one killer of Americans. An estimated one out of three adults is currently living with some form of cardiovascular disease.
Milk provides nine essential nutrients, including calcium, vitamin A, vitamin D, protein and potassium. The U.S. Dietary Guidelines for Americans recommend drinking three glasses of lowfat or fat free milk each day.
Drinking milk may help ease the pressure
New study suggests fat-free milk may offer protection against hypertension -- a rising risk for women in this country
Women who drank more fat free milk and had higher intakes of calcium and vitamin D from foods, and not supplements, tended to have a lower risk for developing hypertension or high blood pressure, according to a new study published in the American Heart Association journal, Hypertension.
After examining the diets of nearly 30,000 middle-aged and older women, Harvard researchers found that women who consumed more low-fat milk and milk products and had diets higher in calcium and vitamin D from foods were better protected against high blood pressure. When the researchers investigated the benefits of milk specifically, they found women who drank two or more servings of fat free milk each day reduced their risk for high blood pressure by up to10 percent compared to those who drank fat free milk less than once a month. The same was not found for higher fat milk and milk products or calcium and vitamin D supplement users.
One in three American adults has high blood pressure, and an increasing number of women are living with undiagnosed hypertension, according to a second study published in the journal Circulation. The last decade has seen significant increases in uncontrolled high blood pressure for women across the nation, a condition that puts them at serious risk for cardiovascular disease, stroke and even kidney failure.
Yet despite a vast body of research linking diet changes to blood pressure control, most Americans are still missing the mark on their diets. According to new research published in the Archives of Internal Medicine, Americans are ignoring the DASH (Dietary Approaches to Stop Hypertension) Diet, the therapeutic eating plan recommended by the National Heart Lung and Blood Institute that emphasizes low-fat dairy, fruits and vegetables to help reduce blood pressure levels.
Saturday, December 13, 2008
Jon's Health Tips - Oatmeal
I eat a big bowl of oatmeal (flavored with organic raisins) almost every day for breakfast. The reasons are outlined below. (I also eat mostly whole wheat bread, and whole wheat pasta when I can, and snack on whole wheat dry cereal once in a while.)
Oatmeal's Health Claims Strongly Reaffirmed
A new scientific review of the most current research shows the link between eating oatmeal and cholesterol reduction to be stronger than when the FDA initially approved the health claim's appearance on food labels in 1997.
Dr. James W. Anderson, professor of medicine and clinical nutrition at the University of Kentucky College of Medicine, co-authors "The Oatmeal-Cholesterol Connection: 10 Years Later" in the January/February 2008 issue of the American Journal of Lifestyle Medicine.
Anderson presents a contemporary analysis to determine if newer studies are consistent with the original conclusion reached by the FDA. His report says studies conducted during the past 15 years have, without exception, shown:_
• total cholesterol levels are lowered through oat consumption;
• low-density lipoprotein (LDL, the "bad" cholesterol) is reduced without adverse effects on high-density lipoprotein cholesterol (HDL, the "good" cholesterol), or triglyceride concentrations.
"Whole-grain products like oatmeal are among some of the best foods one can eat to improve cholesterol levels, in addition to other lifestyle choices," Anderson said. "Lifestyle choices, such as diet, should be the first line of therapy for most patients with moderate cholesterol risk given the expense, safety concerns, and intolerance related to cholesterol lowering drugs.”
More recent data indicate that whole-grain oats, as part of a lifestyle management program, may confer health benefits that extend beyond total cholesterol and LDL cholesterol reduction, Anderson said.
Recent studies suggest eating oatmeal may:_
• Reduce the risk for elevated blood pressure, Type 2 diabetes, and weight gain_
• Reduce LDL cholesterol during weight-loss
• Provide favorable changes in the physical characteristics of LDL cholesterol particles, making them less susceptible to oxidation (oxidation is thought to lead to hardening of the arteries.)
• Supply unique compounds that may lead to reducing early hardening of the arteries
“Since the 80’s, oatmeal has been scientifically recognized for its heart health benefits, and the latest research shows this evidence endures the test of time and should be embraced as a lifestyle option for the millions of Americans at-risk for heart disease,” said Anderson.
Breakfast Improves Overall Diet Quality
A groundbreaking new study shows that eaters of lower energy dense breakfast have improved diet quality, and may have a better ability to maintain a healthy weight.
The study, published in the November 2008 issue of the American Journal of Clinical Nutrition, found that those who enjoy a less energy dense morning meal have diets that are richer in important vitamins and minerals and lower in saturated fat and cholesterol compared to those who consume a more energy dense meal.
The study explored whether or not the energy density -- the number of calories in relation to the grams of foods and beverages -- consumed at breakfast predicted energy density and diet quality for the rest of the day, as well as weight among 12,000 US women and men (as assessed by BMI - body mass index).
“Our new findings carry several important implications concerning breakfast and overall health,” says study co-author, cardiologist Dr. James Rippe of the Rippe Lifestyle Institute. “Our study confirms the findings of many previous studies that eating breakfast helps maintain a healthy weight and provides multiple health benefits. However, what’s unique is that we found lower energy density breakfast foods and beverages high in nutrients, such as whole grain oatmeal and 100 percent orange juice, appear to predict better food choices for the rest of the day and may help with better management of body weight.”
The energy density concept provides new insights into better understanding weight management strategies. Recent studies have reported that individuals with lower energy density diets gain less weight as they age.
Generally, foods with the lowest energy density include fruits, vegetables, soups and whole grains that soak up water, such as oatmeal or rice. Fats and oils, fried foods, desserts, crackers and pretzels are highest in energy density. The more calories per gram of food, equals greater energy density. For example, a breakfast pastry would have more calories per gram (more energy dense) than a bowl of oatmeal and glass of 100% orange juice.
“One simple way to choose breakfast items that are low in energy density is to immediately increase the ratio of high-fiber foods such as fruits, vegetables and whole grains in your morning meal. These foods are less packed with calories, but nutrient-rich, providing a concentrated amount of valuable nutrients to start your day off right,” says Jeff George, vice president of research and development at Quaker Oats.
The study examined the breakfast choices and dietary patterns of a nationally representative sample of 12,000 adults using the most recent National Health and Nutrition Evaluation Survey (NHANES) datasets from 1999-2004 for analyses. Researchers calculated and compared the energy density values for all reported breakfasts and total 24-hour diets among both breakfast eaters and non-eaters.
This research further contributes to the growing body of literature that demonstrates consuming the right foods for breakfast may help with weight management and improve dietary quality. Without breakfast, key nutrients determined by the Dietary Guidelines for Americans are often under-consumed in the daily diet. So it turns out that the recommendation that our mothers gave us is correct – eating breakfast is the most important meal of the day – and choosing more filling and less calorie-dense options at breakfast can make it even more essential for health and well being.
Oatmeal's Health Claims Strongly Reaffirmed
A new scientific review of the most current research shows the link between eating oatmeal and cholesterol reduction to be stronger than when the FDA initially approved the health claim's appearance on food labels in 1997.
Dr. James W. Anderson, professor of medicine and clinical nutrition at the University of Kentucky College of Medicine, co-authors "The Oatmeal-Cholesterol Connection: 10 Years Later" in the January/February 2008 issue of the American Journal of Lifestyle Medicine.
Anderson presents a contemporary analysis to determine if newer studies are consistent with the original conclusion reached by the FDA. His report says studies conducted during the past 15 years have, without exception, shown:_
• total cholesterol levels are lowered through oat consumption;
• low-density lipoprotein (LDL, the "bad" cholesterol) is reduced without adverse effects on high-density lipoprotein cholesterol (HDL, the "good" cholesterol), or triglyceride concentrations.
"Whole-grain products like oatmeal are among some of the best foods one can eat to improve cholesterol levels, in addition to other lifestyle choices," Anderson said. "Lifestyle choices, such as diet, should be the first line of therapy for most patients with moderate cholesterol risk given the expense, safety concerns, and intolerance related to cholesterol lowering drugs.”
More recent data indicate that whole-grain oats, as part of a lifestyle management program, may confer health benefits that extend beyond total cholesterol and LDL cholesterol reduction, Anderson said.
Recent studies suggest eating oatmeal may:_
• Reduce the risk for elevated blood pressure, Type 2 diabetes, and weight gain_
• Reduce LDL cholesterol during weight-loss
• Provide favorable changes in the physical characteristics of LDL cholesterol particles, making them less susceptible to oxidation (oxidation is thought to lead to hardening of the arteries.)
• Supply unique compounds that may lead to reducing early hardening of the arteries
“Since the 80’s, oatmeal has been scientifically recognized for its heart health benefits, and the latest research shows this evidence endures the test of time and should be embraced as a lifestyle option for the millions of Americans at-risk for heart disease,” said Anderson.
Breakfast Improves Overall Diet Quality
A groundbreaking new study shows that eaters of lower energy dense breakfast have improved diet quality, and may have a better ability to maintain a healthy weight.
The study, published in the November 2008 issue of the American Journal of Clinical Nutrition, found that those who enjoy a less energy dense morning meal have diets that are richer in important vitamins and minerals and lower in saturated fat and cholesterol compared to those who consume a more energy dense meal.
The study explored whether or not the energy density -- the number of calories in relation to the grams of foods and beverages -- consumed at breakfast predicted energy density and diet quality for the rest of the day, as well as weight among 12,000 US women and men (as assessed by BMI - body mass index).
“Our new findings carry several important implications concerning breakfast and overall health,” says study co-author, cardiologist Dr. James Rippe of the Rippe Lifestyle Institute. “Our study confirms the findings of many previous studies that eating breakfast helps maintain a healthy weight and provides multiple health benefits. However, what’s unique is that we found lower energy density breakfast foods and beverages high in nutrients, such as whole grain oatmeal and 100 percent orange juice, appear to predict better food choices for the rest of the day and may help with better management of body weight.”
The energy density concept provides new insights into better understanding weight management strategies. Recent studies have reported that individuals with lower energy density diets gain less weight as they age.
Generally, foods with the lowest energy density include fruits, vegetables, soups and whole grains that soak up water, such as oatmeal or rice. Fats and oils, fried foods, desserts, crackers and pretzels are highest in energy density. The more calories per gram of food, equals greater energy density. For example, a breakfast pastry would have more calories per gram (more energy dense) than a bowl of oatmeal and glass of 100% orange juice.
“One simple way to choose breakfast items that are low in energy density is to immediately increase the ratio of high-fiber foods such as fruits, vegetables and whole grains in your morning meal. These foods are less packed with calories, but nutrient-rich, providing a concentrated amount of valuable nutrients to start your day off right,” says Jeff George, vice president of research and development at Quaker Oats.
The study examined the breakfast choices and dietary patterns of a nationally representative sample of 12,000 adults using the most recent National Health and Nutrition Evaluation Survey (NHANES) datasets from 1999-2004 for analyses. Researchers calculated and compared the energy density values for all reported breakfasts and total 24-hour diets among both breakfast eaters and non-eaters.
This research further contributes to the growing body of literature that demonstrates consuming the right foods for breakfast may help with weight management and improve dietary quality. Without breakfast, key nutrients determined by the Dietary Guidelines for Americans are often under-consumed in the daily diet. So it turns out that the recommendation that our mothers gave us is correct – eating breakfast is the most important meal of the day – and choosing more filling and less calorie-dense options at breakfast can make it even more essential for health and well being.
Monday, December 1, 2008
Antioxidants are unlikely to prevent aging
Diets and beauty products which claim to have anti-oxidant properties are unlikely to prevent ageing, according to research funded by the Wellcome Trust. Researchers at the Institute of Healthy Ageing at UCL (University College London) say this is because a key fifty year old theory about the causes of ageing is wrong.
"Superoxide" free radicals – oxygen molecules that have an imbalance of electrons to protons – are generated in the body through natural processes such as metabolism. These free radicals can cause oxidation in the body, analogous to rust when iron is exposed to oxygen. Biological systems, such as the human body, are usually able to restrict or repair this damage.
In 1956, Denham Harman proposed the theory that ageing is caused by an accumulation of molecular damage caused by "oxidative stress", the action of reactive forms of oxygen, such as superoxide, on cells. This theory has dominated the field of ageing research for over fifty years. But now, a study published online today in the journal Genes & Development suggests that this theory is probably incorrect and that superoxide is not a major cause of ageing.
"The fact is that we don't understand much about the fundamental mechanisms of ageing," says Dr David Gems from UCL. "The free radical theory of ageing has filled a knowledge vacuum for over fifty years now, but it just doesn't stand up to the evidence."
Dr Gems and colleagues at the Institute of Healthy Ageing studied the action of key genes involved in removing superoxide from the bodies of the nematode worm C. elegans, a commonly-used model for research into ageing. By manipulating these genes, they were able to control the worm's ability to "mop up" surplus superoxide and limit potential damage caused by oxidation.
Contrary to the result predicted by the free radical theory of ageing, the researchers found that the lifespan of the worm was relatively unaffected by its ability to tackle the surplus superoxide. The findings, combined with similar recent findings from the University of Texas using mice, imply that this theory is incorrect.
"One of the hallmarks of ageing is the accumulation of molecular damage, but what causes this damage?" says Dr Gems. "It's clear that if superoxide is involved, it only plays a small part in the story. Oxidative damage is clearly not a universal, major driver of the ageing process. Other factors, such as chemical reactions involving sugars in our body, clearly play a role."
Dr Gems believes the study suggests that anti-ageing products which claim to have anti-oxidant properties are unlikely to have any effect.
"A healthy, balanced diet is very important for reducing the risk of developing many diseases associated with old age, such as cancer, diabetes and osteoporosis," he says. "But there is no clear evidence that dietary antioxidants can slow or prevent ageing. There is even less evidence to support the claims of most anti-ageing products."
The research was welcomed by Dr Alan Schafer, Head of Molecular and Physiological Sciences at the Wellcome Trust.
"With increasing lifespan comes greater exposure and vulnerability to the ageing process," comments Dr Schafer. "Research such as this points to how much we have to learn about ageing, and the importance of understanding the mechanisms behind this process. This new study will encourage researchers to explore new avenues in ageing research."
"Superoxide" free radicals – oxygen molecules that have an imbalance of electrons to protons – are generated in the body through natural processes such as metabolism. These free radicals can cause oxidation in the body, analogous to rust when iron is exposed to oxygen. Biological systems, such as the human body, are usually able to restrict or repair this damage.
In 1956, Denham Harman proposed the theory that ageing is caused by an accumulation of molecular damage caused by "oxidative stress", the action of reactive forms of oxygen, such as superoxide, on cells. This theory has dominated the field of ageing research for over fifty years. But now, a study published online today in the journal Genes & Development suggests that this theory is probably incorrect and that superoxide is not a major cause of ageing.
"The fact is that we don't understand much about the fundamental mechanisms of ageing," says Dr David Gems from UCL. "The free radical theory of ageing has filled a knowledge vacuum for over fifty years now, but it just doesn't stand up to the evidence."
Dr Gems and colleagues at the Institute of Healthy Ageing studied the action of key genes involved in removing superoxide from the bodies of the nematode worm C. elegans, a commonly-used model for research into ageing. By manipulating these genes, they were able to control the worm's ability to "mop up" surplus superoxide and limit potential damage caused by oxidation.
Contrary to the result predicted by the free radical theory of ageing, the researchers found that the lifespan of the worm was relatively unaffected by its ability to tackle the surplus superoxide. The findings, combined with similar recent findings from the University of Texas using mice, imply that this theory is incorrect.
"One of the hallmarks of ageing is the accumulation of molecular damage, but what causes this damage?" says Dr Gems. "It's clear that if superoxide is involved, it only plays a small part in the story. Oxidative damage is clearly not a universal, major driver of the ageing process. Other factors, such as chemical reactions involving sugars in our body, clearly play a role."
Dr Gems believes the study suggests that anti-ageing products which claim to have anti-oxidant properties are unlikely to have any effect.
"A healthy, balanced diet is very important for reducing the risk of developing many diseases associated with old age, such as cancer, diabetes and osteoporosis," he says. "But there is no clear evidence that dietary antioxidants can slow or prevent ageing. There is even less evidence to support the claims of most anti-ageing products."
The research was welcomed by Dr Alan Schafer, Head of Molecular and Physiological Sciences at the Wellcome Trust.
"With increasing lifespan comes greater exposure and vulnerability to the ageing process," comments Dr Schafer. "Research such as this points to how much we have to learn about ageing, and the importance of understanding the mechanisms behind this process. This new study will encourage researchers to explore new avenues in ageing research."
Good cholesterol isn't good enough
Researchers learn that some 'good cholesterol' isn't good enough
New article in the FASEB Journal describes how the quality of HDL cholesterol is as important as its type
If you think your levels of "good cholesterol" are good enough, a new study published in the December 2008 issue of The FASEB Journal suggests that you may want to think again. In the report, researchers from the University of Chicago challenge the conventional wisdom that simply having high levels of good cholesterol (HDL) and low levels of bad cholesterol (LDL) is necessary for good heath. Instead, they show that the good cholesterol has varying degrees of quality and that poor quality HDL is actually bad for you.
"For many years, HDL has been viewed as good cholesterol and has generated a false perception that the more HDL in the blood, the better," said Angelo Scanu, M.D., a pioneer in blood lipid chemistry from University of Chicago and first author of the study. "It is now apparent that subjects with high HDL are not necessarily protected from heart problems and should ask their doctor to find out whether their HDL is good or bad."
The researchers came to this conclusion after reviewing published research on this subject. In their review, they found that the HDL from people with chronic diseases such as rheumatoid arthritis, kidney disease, and diabetes is different from the HDL in healthy individuals, even when blood levels of HDL are comparable. They observed that normal, "good," HDL reduces inflammation, while the dysfunctional, "bad," HDL does not.
"This is yet one more line of research that explains why some people can have perfect cholesterol levels, but still develop cardiovascular disease," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "Just as the discovery of good and bad cholesterol rewrote the book on cholesterol management, the realization that some of the 'good cholesterol' is actually bad will do the same."
###
According to the U.S. Centers for Disease Control and Prevention, approximately 17 percent of all American adults have high total cholesterol, putting them at risk for heart disease. Cholesterol is a waxy, fat-like substance used by the body to maintain the proper function of cell membranes and is encapsulated within two types of proteins as it travels in the body—low density lipoproteins (LDL) and high density lipoproteins (HDL). High levels of LDL or total cholesterol are an indicator of increased risk for heart disease. High blood cholesterol elicits no physical symptoms, making medical screenings necessary for detection.
New article in the FASEB Journal describes how the quality of HDL cholesterol is as important as its type
If you think your levels of "good cholesterol" are good enough, a new study published in the December 2008 issue of The FASEB Journal suggests that you may want to think again. In the report, researchers from the University of Chicago challenge the conventional wisdom that simply having high levels of good cholesterol (HDL) and low levels of bad cholesterol (LDL) is necessary for good heath. Instead, they show that the good cholesterol has varying degrees of quality and that poor quality HDL is actually bad for you.
"For many years, HDL has been viewed as good cholesterol and has generated a false perception that the more HDL in the blood, the better," said Angelo Scanu, M.D., a pioneer in blood lipid chemistry from University of Chicago and first author of the study. "It is now apparent that subjects with high HDL are not necessarily protected from heart problems and should ask their doctor to find out whether their HDL is good or bad."
The researchers came to this conclusion after reviewing published research on this subject. In their review, they found that the HDL from people with chronic diseases such as rheumatoid arthritis, kidney disease, and diabetes is different from the HDL in healthy individuals, even when blood levels of HDL are comparable. They observed that normal, "good," HDL reduces inflammation, while the dysfunctional, "bad," HDL does not.
"This is yet one more line of research that explains why some people can have perfect cholesterol levels, but still develop cardiovascular disease," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "Just as the discovery of good and bad cholesterol rewrote the book on cholesterol management, the realization that some of the 'good cholesterol' is actually bad will do the same."
###
According to the U.S. Centers for Disease Control and Prevention, approximately 17 percent of all American adults have high total cholesterol, putting them at risk for heart disease. Cholesterol is a waxy, fat-like substance used by the body to maintain the proper function of cell membranes and is encapsulated within two types of proteins as it travels in the body—low density lipoproteins (LDL) and high density lipoproteins (HDL). High levels of LDL or total cholesterol are an indicator of increased risk for heart disease. High blood cholesterol elicits no physical symptoms, making medical screenings necessary for detection.
Friday, November 28, 2008
Jon's Health Tips - Nuts
I eat a handful of nuts several times a week. I am going to try to increase the frequency.
Here’s why:
From Dr. John Livesey, Department of Endocrinology Christchurch Hospital .New Zealand:
“Frequent eating of nuts appears to dramatically improve health1. In particular, nut eating greatly lowers the risk of heart disease2. In 1992 researchers working on the Adventist Health Study at Loma Linda University in California reported that those eating nuts daily had up to 60% fewer heart attacks than those who ate nuts less than once per month3. The beneficial effect of nut consumption was found for men, women, vegetarians, meat-eaters, fatter people, thinner people, the old, the young, those who did much exercise and those who did little exercise. The study was large, comprising 31,000 white Californian Seventh Day Adventists and similar benefits of nut eating were subsequently found for African Americans4. Prior to the publication of these results, nutritional advice had usually been to minimize nut consumption on the grounds that they were a "fatty" food.
Four other large studies have since confirmed the benefits to the heart of nut eating2, 5-8. In addition to the cardiac benefits of consuming nuts, the risks of having a stroke9, of developing type 2 diabetes10, of developing dementia11, of advanced macular degeneration12 and of gallstones 13 have all been found to be lowered by eating nuts. Calculations suggest that daily nut eaters gain an extra five to six years of life free of coronary disease14 and that regular nut eating appears to increase longevity by about 2 years.15.
The more often nuts are eaten the better as the benefits appear to increase as the frequency of nut consumption increases. The risk of fatal coronary disease and the risk of developing type 2 diabetes both appear to decrease steadily as nut consumption increases from less than once a week to once or more per day10, 16.
Just what quantity of nuts should be eaten? The studies above suggest that 30 to 60 grams (1-2oz) of nuts should be consumed daily to gain the maximum benefits seen. Whether even larger amounts confer further benefits is currently unknown.
Nuts are of course a fatty food and many might worry that they will put on weight by eating more nuts. After all, 30 grams (or one ounce) of most nuts contain about 800 kilojoules (200 kilocalories). Happily though, on present evidence, nuts do not seem to cause weight gain1,17. For example in the Nurses' Study the frequent nut consumers were actually a little thinner on average than those who almost never consumed nuts6, and daily supplements of almonds or peanuts for six months resulted in little or no increase in body weight18. Nuts appear to satisfy hunger sufficiently well to appropriately reduce the consumption of other food.
Which nuts are best? The definitive answer to this question is currently unknown. In the Adventist Study about about 32 percent of the nuts eaten were peanuts, 29 percent almonds, 16 percent walnuts, and 23 percent other types. These researchers did not ascertain whether the nuts were fresh, oil-roasted, or dry-roasted. The Nurses' Study found that peanuts, which are legumes, appeared to be just as effective in reducing the risk of coronary heart disease as tree nuts6. Experiments where volunteers were fed nuts as part of their diet for several weeks have found that walnuts19-22, almonds22-25, hazelnuts26, peanuts27, pecans28, pistachio nuts29 and macadamia nuts30 all alter the composition of the blood in ways that would be expected to reduce the risk of coronary disease. Chestnuts, a nut unusually low in fat, do not yet seem to have been studied. The best advice currently is probably to eat a variety of nuts.”
Researchers found that people who eat nuts regularly have lower risks of heart disease. In 1996, the Iowa Women's Healthy Study found that women who ate nuts more than 4 times a week were 40% less likely to die of heart disease. Two years later, another study conducted by the Harvard School of Public Health found a similar result in another group of women subjects. Furthermore, potential heart health benefits of nuts were also found among men. In 2002, the Physician's Health Study found that men who consumed nuts 2 or more times per week had reduced risks of sudden cardiac death.
FDA only approved the heart health claim for almonds, hazelnuts, peanuts, pecans, some pine nuts, pistachios and walnuts as these nuts contain less than 4g of saturated fats per 50g. The FDA said: "Scientific evidence suggests but does not prove that eating 1.5 oz per day of most nuts as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease."
Here’s why:
From Dr. John Livesey, Department of Endocrinology Christchurch Hospital .New Zealand:
“Frequent eating of nuts appears to dramatically improve health1. In particular, nut eating greatly lowers the risk of heart disease2. In 1992 researchers working on the Adventist Health Study at Loma Linda University in California reported that those eating nuts daily had up to 60% fewer heart attacks than those who ate nuts less than once per month3. The beneficial effect of nut consumption was found for men, women, vegetarians, meat-eaters, fatter people, thinner people, the old, the young, those who did much exercise and those who did little exercise. The study was large, comprising 31,000 white Californian Seventh Day Adventists and similar benefits of nut eating were subsequently found for African Americans4. Prior to the publication of these results, nutritional advice had usually been to minimize nut consumption on the grounds that they were a "fatty" food.
Four other large studies have since confirmed the benefits to the heart of nut eating2, 5-8. In addition to the cardiac benefits of consuming nuts, the risks of having a stroke9, of developing type 2 diabetes10, of developing dementia11, of advanced macular degeneration12 and of gallstones 13 have all been found to be lowered by eating nuts. Calculations suggest that daily nut eaters gain an extra five to six years of life free of coronary disease14 and that regular nut eating appears to increase longevity by about 2 years.15.
The more often nuts are eaten the better as the benefits appear to increase as the frequency of nut consumption increases. The risk of fatal coronary disease and the risk of developing type 2 diabetes both appear to decrease steadily as nut consumption increases from less than once a week to once or more per day10, 16.
Just what quantity of nuts should be eaten? The studies above suggest that 30 to 60 grams (1-2oz) of nuts should be consumed daily to gain the maximum benefits seen. Whether even larger amounts confer further benefits is currently unknown.
Nuts are of course a fatty food and many might worry that they will put on weight by eating more nuts. After all, 30 grams (or one ounce) of most nuts contain about 800 kilojoules (200 kilocalories). Happily though, on present evidence, nuts do not seem to cause weight gain1,17. For example in the Nurses' Study the frequent nut consumers were actually a little thinner on average than those who almost never consumed nuts6, and daily supplements of almonds or peanuts for six months resulted in little or no increase in body weight18. Nuts appear to satisfy hunger sufficiently well to appropriately reduce the consumption of other food.
Which nuts are best? The definitive answer to this question is currently unknown. In the Adventist Study about about 32 percent of the nuts eaten were peanuts, 29 percent almonds, 16 percent walnuts, and 23 percent other types. These researchers did not ascertain whether the nuts were fresh, oil-roasted, or dry-roasted. The Nurses' Study found that peanuts, which are legumes, appeared to be just as effective in reducing the risk of coronary heart disease as tree nuts6. Experiments where volunteers were fed nuts as part of their diet for several weeks have found that walnuts19-22, almonds22-25, hazelnuts26, peanuts27, pecans28, pistachio nuts29 and macadamia nuts30 all alter the composition of the blood in ways that would be expected to reduce the risk of coronary disease. Chestnuts, a nut unusually low in fat, do not yet seem to have been studied. The best advice currently is probably to eat a variety of nuts.”
Researchers found that people who eat nuts regularly have lower risks of heart disease. In 1996, the Iowa Women's Healthy Study found that women who ate nuts more than 4 times a week were 40% less likely to die of heart disease. Two years later, another study conducted by the Harvard School of Public Health found a similar result in another group of women subjects. Furthermore, potential heart health benefits of nuts were also found among men. In 2002, the Physician's Health Study found that men who consumed nuts 2 or more times per week had reduced risks of sudden cardiac death.
FDA only approved the heart health claim for almonds, hazelnuts, peanuts, pecans, some pine nuts, pistachios and walnuts as these nuts contain less than 4g of saturated fats per 50g. The FDA said: "Scientific evidence suggests but does not prove that eating 1.5 oz per day of most nuts as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease."
Monday, November 24, 2008
Gasping after collapse - CPR should be initiated
Gasping helps cardiac arrest victims survive
Gasping should not be mistaken for breathing and CPR should be initiated
People who witness an individual collapse suddenly and unexpectedly should perform uninterrupted chest compressions even if the patient gasps or breathes in a funny way, research from the Resuscitation Research Group at The University of Arizona Sarver Heart Center shows. The study is set to publish in the Nov. 24 online issue of Circulation, the official journal of the American Heart Association, http://circ.ahajournals.org.
When an individual breathes abnormally or gasps after collapsing from sudden cardiac arrest there is a greater chance of surviving, the researchers report. Gasping can be thought of as a survival reflex triggered by the brain.
Each day, about 500 Americans collapse because their hearts suddenly stop beating. Data collected by Sarver Heart Center researchers show that in more than half of witnessed cardiac arrest cases, the patient gasped.
"Gasping is an indication that the brain is still alive, and it tells you that if you start and continue uninterrupted chest compressions, the person has a high chance of surviving," said Gordon A. Ewy, MD, corresponding author of the study, professor and chief of cardiology at the UA and director of its Sarver Heart Center. "We need people to promptly recognize sudden cardiac arrest, to call 9-1-1 and to start chest compressions right away."
Gasping has been described as snoring, gurgling, moaning, snorting or agonal or labored breathing. However, bystanders often misinterpret gasping and other unusual vocal sounds as normal breathing and don't call 9-1-1 or begin lifesaving chest compressions quickly enough, Dr. Ewy said.
The authors hope their findings lead to greater willingness of untrained bystanders to jump in and perform continuous chest compressions. Bystander-initiated CPR has been shown to be a cardiac arrest victim's only chance of survival until an automated external defibrillator or the paramedics get to the scene.
Many bystanders are hesitant to perform mouth-to-mouth ventilation, and in a case of a witnessed (seen or heard) collapse, so-called rescue breathing is not necessary and may be harmful, Dr. Ewy said. "When the patient gasps, there is a negative pressure in the chest, which not only sucks air into the lungs but also draws blood back to the heart. In contrast, mouth-to-mouth breathing creates overpressure in the chest and actually inhibits blood flow back to the heart. Gasping during cardiac arrest is much better than mouth-to-mouth breathing."
But what about choking? "That's very different," Dr. Ewy said. "Someone who is choking will be seen to grasp their throat and struggle to breathe, which means they're responsive. These individuals need the Heimlich maneuver." A primary cardiac arrest is the witnessed unexpected collapse of an individual who is not responsive, Dr. Ewy said. "Cardiac arrest will cause the stricken individual to pass out and collapse to the ground within seconds."
The Arizona researchers examined data from two sources. Transcripts from the Phoenix Fire Department Regional Dispatch Center included information on gasping in patients found by bystanders, whether their collapse was witnessed or not. The department's first-care reports on 1,218 witnessed patients provided the incidence of gasping upon or after the arrival of emergency medical service (EMS) personnel. Among the 481 patients who received bystander CPR, 39 percent of gaspers survived, but only 9.4 percent of those who didn't gasp survived.
Performing uninterrupted chest compressions (a technique developed at the UA Sarver Heart Center and endorsed by the American Heart Association as "Hands-Only CPR" for lay individuals) may cause a person who has stopped gasping to resume gasping. "This scares many people and they stop pressing on the chest," Dr. Ewy said, "This is bad because gasping is an indication that you're doing a good job."
Gasping should not be mistaken for breathing and CPR should be initiated
People who witness an individual collapse suddenly and unexpectedly should perform uninterrupted chest compressions even if the patient gasps or breathes in a funny way, research from the Resuscitation Research Group at The University of Arizona Sarver Heart Center shows. The study is set to publish in the Nov. 24 online issue of Circulation, the official journal of the American Heart Association, http://circ.ahajournals.org.
When an individual breathes abnormally or gasps after collapsing from sudden cardiac arrest there is a greater chance of surviving, the researchers report. Gasping can be thought of as a survival reflex triggered by the brain.
Each day, about 500 Americans collapse because their hearts suddenly stop beating. Data collected by Sarver Heart Center researchers show that in more than half of witnessed cardiac arrest cases, the patient gasped.
"Gasping is an indication that the brain is still alive, and it tells you that if you start and continue uninterrupted chest compressions, the person has a high chance of surviving," said Gordon A. Ewy, MD, corresponding author of the study, professor and chief of cardiology at the UA and director of its Sarver Heart Center. "We need people to promptly recognize sudden cardiac arrest, to call 9-1-1 and to start chest compressions right away."
Gasping has been described as snoring, gurgling, moaning, snorting or agonal or labored breathing. However, bystanders often misinterpret gasping and other unusual vocal sounds as normal breathing and don't call 9-1-1 or begin lifesaving chest compressions quickly enough, Dr. Ewy said.
The authors hope their findings lead to greater willingness of untrained bystanders to jump in and perform continuous chest compressions. Bystander-initiated CPR has been shown to be a cardiac arrest victim's only chance of survival until an automated external defibrillator or the paramedics get to the scene.
Many bystanders are hesitant to perform mouth-to-mouth ventilation, and in a case of a witnessed (seen or heard) collapse, so-called rescue breathing is not necessary and may be harmful, Dr. Ewy said. "When the patient gasps, there is a negative pressure in the chest, which not only sucks air into the lungs but also draws blood back to the heart. In contrast, mouth-to-mouth breathing creates overpressure in the chest and actually inhibits blood flow back to the heart. Gasping during cardiac arrest is much better than mouth-to-mouth breathing."
But what about choking? "That's very different," Dr. Ewy said. "Someone who is choking will be seen to grasp their throat and struggle to breathe, which means they're responsive. These individuals need the Heimlich maneuver." A primary cardiac arrest is the witnessed unexpected collapse of an individual who is not responsive, Dr. Ewy said. "Cardiac arrest will cause the stricken individual to pass out and collapse to the ground within seconds."
The Arizona researchers examined data from two sources. Transcripts from the Phoenix Fire Department Regional Dispatch Center included information on gasping in patients found by bystanders, whether their collapse was witnessed or not. The department's first-care reports on 1,218 witnessed patients provided the incidence of gasping upon or after the arrival of emergency medical service (EMS) personnel. Among the 481 patients who received bystander CPR, 39 percent of gaspers survived, but only 9.4 percent of those who didn't gasp survived.
Performing uninterrupted chest compressions (a technique developed at the UA Sarver Heart Center and endorsed by the American Heart Association as "Hands-Only CPR" for lay individuals) may cause a person who has stopped gasping to resume gasping. "This scares many people and they stop pressing on the chest," Dr. Ewy said, "This is bad because gasping is an indication that you're doing a good job."
Saturday, November 22, 2008
Jon's Health Tips - Vitamin D
I have recently added a new pill to the few I take daily – a major decision for me. But the spate of recent research is so overwhelming that I had to do it. I have also made an effort to get more sun in the cold months, eat more dairy products, especially no-fat yogurt, and drink only fortified orange juice. The pill is Vitamin D. The recent research is summarized very briefly below. A complete report is available at
Low Vitamin D Levels Pose Large Threat to Health; Overall 26 Percent Increased Risk of Death
Researchers at Johns Hopkins are reporting what is believed to be the most conclusive evidence to date that inadequate levels of vitamin D, obtained from milk, fortified cereals and exposure to sunlight, lead to substantially increased risk of death.
In a study set to appear in the Archives of Internal Medicine online Aug. 11, the Johns Hopkins team analyzed a diverse sample of 13,000 initially healthy men and women participating in an ongoing national health survey and compared the risk of death between those with the lowest blood levels of vitamin D to those with higher amounts. An unhealthy deficiency, experts say, is considered blood levels of 17.8 nanograms per milliliter or lower.
Of the 1,800 study participants known to have died by Dec. 31, 2000, nearly 700 died from some form of heart disease, with 400 of these being deficient in vitamin D. This translates overall to an estimated 26 percent increased risk of any death, though the number of deaths from heart disease alone was not large enough to meet scientific criteria to resolve that it was due to low vitamin D levels.
Yet, researchers say it does highlight a trend, with other studies linking shortages of vitamin D to increased rates of breast cancer and depression in the elderly. And earlier published findings by the team, from the same national study, have established a possible tie-in, showing an 80 percent increased risk of peripheral artery disease from vitamin D deficits.
Researchers note that other studies in the last year or so in animals and humans have identified a connection between low levels of vitamin D and heart disease. But these studies, they say, were weakened by small sample numbers, lack of diversity in the population studied and other factors that limited scientists' ability to generalize the findings to the public at large.
"Our results make it much more clear that all men and women concerned about their overall health should more closely monitor their blood levels of vitamin D, and make sure they have enough," says study co-lead investigator Erin Michos, M.D., M.H.S.
"We think we have additional evidence to consider adding vitamin D deficiency as a distinct and separate risk factor for death from cardiovascular disease, putting it alongside much better known and understood risk factors, such as age, gender, family history, smoking, high blood cholesterol levels, high blood pressure, lack of exercise, obesity and diabetes," says Michos. Vitamin D is well known to play an essential role in cell growth, in boosting the body's immune system and in strengthening bones.
"Now that we know vitamin D deficiency is a risk factor, we can better assess how aggressively to treat people at risk of heart disease or those who are already ill and undergoing treatment," says Michos, who adds that test screening for nutrient levels is relatively simple. It can, she says, be made part of routine blood work and done while monitoring other known risk factors, including blood pressure, glucose and lipid levels.
Heart disease remains the nation's leading cause of death, killing more than a million Americans each year. Nearly 10 percent of those with the condition have not one identifiable, traditional risk factor, which the experts say is why a considerable extent of the disease goes unexplained.
Michos, an assistant professor at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute, recommends that people boost their vitamin D levels by eating diets rich in such fish as sardines and mackerel, consuming fortified dairy products, taking cod-liver oil and vitamin supplements, and in warmer weather briefly exposing skin to the sun's vitamin-D producing ultraviolet light.
Aware of the cancer risks linked to too much time spent in the sun, she says as little as 10 to 15 minutes of daily exposure to the sun can produce sufficient amounts of vitamin D to sustain health. The hormone-like nutrient controls blood levels of calcium and phosphorus, essential chemicals in the body.
If vitamin supplements are used, Michos says there is no evidence that more than 2,000 international units per day do any good. Study results show that heart disease death rates flattened out in participants with the highest vitamin D levels (above 50 nanograms per milliliter of blood), signaling a possible loss of the vitamin's protective effects at too-high doses.
The U.S. Institute of Medicine suggests that an adequate daily intake of vitamin D is between 200 and 400 international units (or blood levels nearing 30 nanograms per milliliter). Previous results from the same nationwide survey showed that 41 percent of men and 53 percent of women are technically deficient in the nutrient, with vitamin D levels below 28 nanograms per milliliter.
Michal Melamed, M.D., M.H.S., study co-lead investigator who started the research as a clinical fellow at Johns Hopkins, says no one knows yet why or how vitamin D's hormone-like properties may protect the heart, but she adds that there are plenty of leads in the better known links the vitamin has to problems with muscle overgrowth and high blood pressure, in addition to its control of inflammation, which scientists are showing plays a stronger role in all kinds of heart disease. But more research is needed to determine the nutrient's precise biological action.
Researchers say their next steps are to test various high doses of vitamin D to find out if the nutritional supplementation results in fewer deaths and lower incidence of heart disease, including heart attack or moments of prolonged and severe chest pain.
The team also plans to investigate what biological triggers, such as obesity or hypertension, might offset or worsen the action of vitamin D on heart muscle, or whether vitamin D sets off some other reaction in the heart.
Melamed says that because vitamin D levels are known to fluctuate in direct proportion with daily physical activity, the growing epidemic of obesity and indoor sedentary lifestyles lend more urgency to act on the vitamin D factor.
Vitamin D a key player in overall health of several body organs
Essential for life in higher animals, vitamin D, once linked to only bone diseases such as rickets and osteoporosis, is now recognized as a major player in contributing to overall human health, emphasizes UC Riverside's Anthony Norman, an international expert on vitamin D.
In a paper published in the August issue of the American Journal of Clinical Nutrition, Norman identifies vitamin D's potential for contributions to good health in the adaptive and innate immune systems, the secretion and regulation of insulin by the pancreas, the heart and blood pressure regulation, muscle strength and brain activity. In addition, access to adequate amounts of vitamin D is believed to be beneficial towards reducing the risk of cancer.
Norman also lists 36 organ tissues in the body whose cells respond biologically to vitamin D. The list includes bone marrow, breast, colon, intestine, kidney, lung, prostate, retina, skin, stomach and the uterus.
According to Norman, deficiency of vitamin D can impact all 36 organs. Already, vitamin D deficiency is associated with muscle strength decrease, high risk for falls, and increased risk for colorectal, prostate and breast and other major cancers.
"It is becoming increasingly clear to researchers in the field that vitamin D is strongly linked to several diseases," said Norman, a distinguished professor emeritus of biochemistry and of biomedical sciences who has worked on vitamin D for more than 45 years. "Its biological sphere of influence is much broader than we originally thought. The nutritional guidelines for vitamin D intake must be carefully reevaluated to determine the adequate intake, balancing sunlight exposure with dietary intake, to achieve good health by involving all 36 target organs."
Vitamin D is synthesized in the body in a series of steps. First, sunlight's ultraviolet rays act on a precursor compound in skin. When skin is exposed to sunlight, a sterol present in dermal tissue is converted to vitamin D, which, in turn, is metabolized in the liver and kidneys to form a hormone. It was Norman's laboratory that discovered, in 1967, that vitamin D is converted into a steroid hormone by the body.
The recommended daily intake of vitamin D is 200 international units (IU) for people up to 50 years old. The recommended daily intake of vitamin D is 400 IU for people 51 to 70 years old and 600 IU for people over 70 years old. Norman's recommendation for all adults is to have an average daily intake of at least 2000 IU.
"To optimize good health you must have enough vitamin D," he said. "Vitamin D deficiency is also especially of concern in third world countries that have poor nutritional practices and religious customs that require the body to be covered from head to toe. Ideally, to achieve the widest frequency of good health by population, we need to have 90 percent of the people with adequate amounts of vitamin D."
About half of the elderly in North America and two-thirds of the rest of the world are not getting enough vitamin D to maintain healthy bone density, lower their risks for fracture and improve tooth attachment.
"There needs to be a sea change by various governmental agencies in terms of the advice they present to citizens about how much vitamin D should be taken," Norman said. "The tendencies of people to live in cities where tall buildings block adequate sunlight from reaching the ground, to spend most of their time indoors, to use synthetic sunscreens that block ultraviolet rays, and to live in geographical regions of the world that do not receive adequate sunlight all contribute to the inability of the skin to biosynthesize sufficient amounts of vitamin D."
Found in minute amounts in food, vitamins are organic substances that higher forms of animals need to grow and sustain normal health. Vitamins, however, are not synthesized in sufficient amounts to meet bodily needs. Therefore, the body must acquire them through diet or in the form of supplements.
Because it is found in very few foods naturally, milk and other foods (often orange juice) are fortified with vitamin D.
While deficiency of vitamin D impacts health negatively, ingestion of extremely high doses of vitamin D can cause hypercalcemia, a condition in which the blood's calcium level is above normal. The highest daily 'safe' dose of vitamin D is 10,000 IU.
"More than ever we need to increase the amount of research on vitamin D, with more funding from government agencies and pharmaceutical companies, to meet the challenge of preserving or improving the health of everyone on the planet," Norman said.
Lack of vitamin D linked to Parkinson's disease
A majority of Parkinson's disease patients had insufficient levels of vitamin D in a new study from Emory University School of Medicine.
The fraction of Parkinson's patients with vitamin D insufficiency, 55 percent, was significantly more than patients with Alzheimer's disease (41 percent) or healthy elderly people (36 percent).
The results are published in the October issue of Archives of Neurology.
The finding adds to evidence that low vitamin D is associated with Parkinson's, says first author Marian Evatt, MD, assistant professor of neurology at Emory.
Evatt is assistant director of the Movement Disorders Program at Wesley Woods Hospital. The senior author is endocrinologist Vin Tangpricha, MD, assistant professor of medicine at Emory and director of the Endocrine Clinical Research Unit.
Evatt says her team compared Parkinson's patients to Alzheimer's patients because they wanted to evaluate the possibility that neurodegenerative diseases in general lead to vitamin D insufficiency.
Most Americans get the majority of their vitamin D from exposure to sunlight or by dietary supplements; fortified foods such as milk and packaged cereals are a minor source. Only a few foods in nature contain substantial amounts of vitamin D, such as salmon and tuna.
The body's ability to produce vitamin D using UV-B radiation from the sun decreases with age, making older individuals at increased risk of vitamin D deficiency.
"We found that vitamin D insufficiency may have a unique association with Parkinson's, which is intriguing and warrants further investigation," Evatt says.
The connection could come partly because patients with Parkinson's have mobility problems and are seldom exposed to the sun, or because low vitamin D levels are in some way related to the genesis or progression of the disease.
She says her team saw their results as striking because their study group came from the Southeast, not a region with long gloomy winters, where vitamin D insufficiency is thought to be more of a problem.
In addition, the study found that the fraction of patients with the lowest levels of vitamin D, described as vitamin D deficiency, was higher (23 percent) in the Parkinson's group than the Alzheimer's group (16 percent) or the healthy group (10 percent).
The retrospective study examined 100 people in each group, who were recruited between 1992 and 2007. Every fifth Parkinson's patient from Emory's clinical neurology database was selected, then healthy controls and patients with Alzheimer's disease were matched on age and state of residence.
Vitamin D insufficiency is frequently defined as less than 30 nanograms per milliliter of blood of the 25-hydroxy form (the major storage form) of the vitamin and deficiency as less than 20 nanograms per milliliter. However, most experts agree insufficiency warrants treatment and should not be ignored.
Doctors have known for decades that vitamin D plays a role in bone formation, Evatt says. More recently, scientists have been uncovering its effects elsewhere, including producing peptides that fight microbes in the skin, regulating blood pressure and insulin levels, and maintaining the nervous system. Low vitamin D levels also appear to increase the risk of several cancers and auto-immune diseases such as multiple sclerosis and diabetes.
Parkinson's disease affects nerve cells in several parts of the brain, particularly those that use the chemical messenger dopamine to control movement. The most common symptoms are tremor, stiffness and slowness of movement. These can be treated with oral replacement of dopamine.
Previous studies have shown that the part of the brain affected most by Parkinson's, the substantia nigra, has high levels of the vitamin D receptor, which suggests vitamin D may be important for normal functions of these cells, Evatt says.
Emory clinicians are conducting further research to investigate whether vitamin D insufficiency is a cause or possibly a result of having Parkinson's. In a pilot study, Parkinson's patients are receiving either standard or larger doses of vitamin D, with an eye towards possibly reducing the severity of their condition.
Current Vitamin D Recommendations Merely a Fraction of Safe and Perhaps Essential Levels for Children
The current recommended daily allowance (RDA) of vitamin D for children is 200 International Units (IUs), but new research reveals that children may need and can safely take ten-times that amount. According to a recently accepted report in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM), this order-of-magnitude increase could improve the bone health of children worldwide and may have other long-term health benefits.
“Our research reveals that vitamin D, at doses equivalent to 2,000 IUs a day, is not only safe for adolescents, but it is actually necessary for achieving desirable vitamin D levels,” said Ghada El-Haff Fuleihan, M.D., of the American University of Beirut-Medical Center, Lebanon, and lead author of the study.
Vitamin D is an essential hormone for bone growth and development in children and promotes skeletal health in adults. Currently, the National Academy of Sciences’ Institute of Medicine recommends an adequate daily intake of 200 IUs of vitamin D for children. This is also the recommendation from the American Academy of Pediatrics. These levels, however, may not be adequate for bone growth and musculoskeletal health in children and adolescents.
“Data on appropriate vitamin D levels in the pediatric age group are lacking,” said Dr. Fuleihan. “This is a major obstacle to finding the right daily allowance to enhance musculoskeletal health.”
To help clarify these important guidelines, Fuleihan and his colleagues conducted both short- and long-term trials to gauge the safety of relatively high doses of vitamin D3 in children ages 10-17 years.
Vitamin D3 is one of the most common forms of vitamin D, and is easily converted to 25-OHD (25-hydroxyvitamin), which is the active form of vitamin D found in the blood.
For this placebo-controlled study, researchers gave children various doses of vitamin D at various intervals and measured the impact this had on serum levels of 25-OHD.
For the short-term study, 25 students (15 boys and 10 girls) received one-weekly, 14,000 IU doses of vitamin D for eight weeks. Serum levels of 25-OHD were then measured for an additional eight weeks. This portion of the test was conducted during the summer and early fall, when the highest natural levels of vitamin D are reached.
For the long-term, one-year study, 340 students (172 boys and 168 girls) received either a low dose of vitamin D (1,400 IUs each week) or a high dose (14,000 IUs each week).
Only children given the equivalent of 2,000 IUs a day of vitamin D increased 25-OHD levels from the mid-teens to the mid-thirties (ng/ml)—the level considered optimal for adults. None of the children in either trial showed any evidence for vitamin D intoxication.
Although many experts agree that a 25-OHD level of 30 ng/ml is desirable in adults, what constitutes an optimal D level for children and adolescents is more debatable. According to the researchers, due to rapid skeletal growth, children and adolescents are more likely to be vitamin D deficient, and are far less likely to reach vitamin D levels that doctors would consider toxic.
“Supplementation of children and adolescents with 2,000 IUs a day of vitamin D3 is well tolerated and safe,” said Dr. Fuleihan. “This is particularly relevant in light of the increasingly recognized health benefits of vitamin D for adults and children.”
Other researchers involved in the study include Joyce Maalouf, Mona Nabulsi, Reinhold Vieth, Samantha Kimball, Rola El-Rassi, and Ziyad Mahfoud.
The study “Short term and long term safety of weekly high dose vitamin D3 supplemetnation in school children” will be published in the July issue of JCEM.
Oral vitamin D may help prevent some skin infections
A study led by researchers at the University of California, San Diego School of Medicine suggests that use of oral Vitamin D supplements bolsters production of a protective chemical normally found in the skin, and may help prevent skin infections that are a common result of atopic dermatitis, the most common form of eczema.
The study – led by Richard Gallo, M.D., Ph.D., professor of medicine and chief of the Division of Dermatology at the UCSD School of Medicine and the Dermatology section of the Veterans Affairs San Diego Healthcare System, and Tissa R. Hata, M.D., associate professor of medicine at UC San Diego – found that use of oral vitamin D appeared to correct a defect in the immune systems in patients with this skin disease. Their findings will be published in the October 3 edition of the Journal of Allergy & Clinical Immunology
The researchers studied a small number of patients with moderate to severe atopic dermatitis, a chronic skin disease that affects 10 to 20 percent of children and one to three percent of adults. Atopic dermatitis is characterized by areas of severe itching, redness and scaling. Over time, chronic changes can occur due to constant scratching and rubbing. The condition puts patients at increased risk for skin infections by Staph aureus and the herpes and small pox viruses.
It had previously been shown that defects in the immune system interfere with the skin's ability to produce a peptide called cathelicidin, which is protective against microbial invasion. In many skin diseases, including eczema, a deficiency of cathelicidin correlates with increased infection.
Study participants (14 with atopic dermatitis and 14 without) were all given 4000 IUs of oral Vitamin D3 (cholecalciferol) per day for 21 days. Skin lesions were biopsied before and after the 21-day period. The researchers found that oral vitamin D use by the patients appeared to correct the skin's defect in cathelicidin.
"These results suggest that supplementation with oral vitamin D dramatically induces cathelicidin production in the skin of patients with atopic dermatitis," said Hata. "It also slightly elevated its production in normal skin in this study."
However, the researchers caution that this was a small study and that further research is needed to evaluate the long-term effects of vitamin D supplementation, and to determine if this may be an adequate way to prevent infections in patients with atopic dermatitis.
In the past several years, vitamin D deficiency has been linked to increased rates of multiple cancers and diabetes, among other diseases, notably in studies published by UC San Diego researcher, Cedric Garland, Dr. P.H., professor with Moores UCSD Cancer Center and the Department of Family and Preventive Medicine at UC San Diego.
Vitamin D findings point to new treatment for heart failure
Strong bones, a healthy immune system, protection against some types of cancer: Recent studies suggest there’s yet another item for the expanding list of Vitamin D benefits. Vitamin D, “the sunshine vitamin,” keeps the heart, the body’s long-distance runner, fit for life’s demands.
University of Michigan pharmacologist Robert U. Simpson, Ph.D., thinks it’s apt to call vitamin D “the heart tranquilizer.”
In studies in rats, Simpson and his team report the first concrete evidence that treatment with activated vitamin D can protect against heart failure. Their results appear in the July issue of the Journal of Cardiovascular Pharmacology.
In the study, treatments with activated vitamin D prevented heart muscle cells from growing bigger – the condition, called hypertrophy, in which the heart becomes enlarged and overworked in people with heart failure. The treatments prevented heart muscle cells from the over-stimulation and increased contractions associated with the progression of heart failure.
Simpson and his colleagues have explored vitamin D’s effects on heart muscle and the cardiovascular system for more than 20 years. In 1987, when Simpson showed the link between vitamin D and heart health, the idea seemed far-fetched and research funding was scarce. Now, a number of studies worldwide attest to the vitamin D-heart health link (see citations below).
The new heart insights add to the growing awareness that widespread vitamin D deficiency—thought to affect one-third to one-half of U.S. adults middle-aged and older—may be putting people at greater risk of many common diseases. Pharmaceutical companies are developing anti-cancer drugs using vitamin D analogs, which are synthetic compounds that produce vitamin D’s effects. There’s also increasing interest in using vitamin D or its analogs to treat autoimmune disorders.
In more than a dozen types of tissues and cells in the body, activated vitamin D acts as a powerful hormone, regulating expression of essential genes and rapidly activating already expressed enzymes and proteins. In the heart, Simpson’s team has revealed precisely how activated vitamin D connects with specific vitamin D receptors and produces its calming, protective effects. Those results appeared in the February issue of Endocrinology.
Sunlight causes the skin to make activated vitamin D. People also get vitamin D from certain foods and vitamin D supplements. Taking vitamin D supplements and for many people, getting sun exposure in safe ways, are certainly good options for people who want to keep their hearts healthy. But people with heart failure or at risk of heart failure will likely need a drug made of a compound or analog of vitamin D that will more powerfully produce vitamin D’s effects in the heart if they are to see improvement in their symptoms, Simpson says.
Vitamin D analogs already are on the market for some conditions. One present drawback of these compounds is that they tend to increase blood calcium to undesirable levels. Simpson’s lab is conducting studies of a specific analog which may be less toxic, so efforts to develop a vitamin D-based drug to treat heart failure are moving a step closer to initial trials in people.
Men with vitamin D deficiency may have increased risk of heart attack
Low levels of vitamin D appear to be associated with higher risk of myocardial infarction (heart attack) in men, according to a report in the June 9 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Studies have shown that the rates of cardiovascular disease-related deaths are increased at higher latitudes and during the winter months and are lower at high altitudes, according to background information in the article. "This pattern is consistent with an adverse effect of hypovitaminosis D [vitamin D deficiency], which is more prevalent at higher latitudes, during the winter and at lower altitudes," the authors write. While other explanations are possible, vitamin D has been shown to affect the body in ways that may influence the risk of heart attack or heart disease.
Edward Giovannucci, M.D., Sc.D., of Harvard School of Public Health and Brigham and Women's Hospital, Boston, and colleagues reviewed medical records and blood samples of 454 men (age 40 to 75) who had non-fatal heart attack or fatal heart disease from the date of blood collection (between January 1993 and December 1995) until January 2004. They then compared the data from these men with records and blood samples of 900 living men who did not have a history of cardiovascular disease. The men's diet and lifestyle factors, recorded by self-administered questionnaires were also noted.
Men with a vitamin D deficiency (having 15 nanograms per milliliter of blood or less) had an increased risk for heart attack compared with those with a sufficient amount (having 30 nanograms per milliliter of blood or more) of vitamin D. "After additional adjustment for family history of myocardial infarction, body mass index, alcohol consumption, physical activity, history of diabetes mellitus and hypertension, ethnicity, region, marine omega 3 intake, low- and high-density lipoprotein cholesterol levels and triglyceride levels, this relationship remained significant," the authors write. Men with intermediate levels of vitamin D had a higher risk of heart attack than those with sufficient vitamin D levels.
"Vitamin D deficiency has been related to an increasing number of conditions and to total mortality. These results further support an important role for vitamin D in myocardial infarction risk," the authors conclude. "Thus, the present findings add further support that the current dietary requirements of vitamin D need to be increased to have an effect on circulating 25(OH)D [vitamin D] levels substantially large enough for potential health benefits."
2 new studies back vitamin D for cancer prevention
Two new vitamin D studies using a sophisticated form of analysis called meta-analysis, in which data from multiple reports is combined, have revealed new prescriptions for possibly preventing up to half of the cases of breast cancer and two-thirds of the cases of colorectal cancer in the United States. The work was conducted by a core team of cancer prevention specialists at the Moores Cancer Center at University of California, San Diego (UCSD), and colleagues from both coasts.
The breast cancer study, published online in the current issue of the Journal of Steroid Biochemistry and Molecular Biology, pooled dose-response data from two earlier studies - the Harvard Nurses Health Study and the St. George's Hospital Study - and found that individuals with the highest blood levels of 25-hydroxyvitamin D, or 25(OH)D, had the lowest risk of breast cancer._
The researchers divided the 1,760 records of individuals in the two studies into five equal groups, from the lowest blood levels of 25(OH)D (less than 13 nanograms per milliliter, or 13 ng/ml) to the highest (approximately 52 ng/ml). The data also included whether or not the individual had developed cancer.
"The data were very clear, showing that individuals in the group with the lowest blood levels had the highest rates of breast cancer, and the breast cancer rates dropped as the blood levels of 25-hydroxyvitamin D increased," said study co-author Cedric Garland, Dr.P.H. "The serum level associated with a 50 percent reduction in risk could be maintained by taking 2,000 international units of vitamin D3 daily plus, when the weather permits, spending 10 to 15 minutes a day in the sun."
The colorectal cancer study, published online February 6 in the American Journal of Preventive Medicine, is a meta-analysis of five studies that explored the association of blood levels of 25(OH)D with risk of colon cancer. All of the studies involved blood collected and tested for 25 (OH)D levels from healthy volunteer donors who were then followed for up to 25 years for development of colorectal cancer._
As with the breast cancer study, the dose-response data on a total of 1,448 individuals were put into order by serum 25(OH)D level and then divided into five equal groups, from the lowest blood levels to the highest.
"Through this meta-analysis we found that raising the serum level of 25-hydroxyvitamin D to 34 ng/ml would reduce the incidence rates of colorectal cancer by half," said co-author Edward D. Gorham, Ph.D. "We project a two-thirds reduction in incidence with serum levels of 46ng/ml, which corresponds to a daily intake of 2,000 IU of vitamin D3. This would be best achieved with a combination of diet, supplements and 10 to 15 minutes per day in the sun."_
Vitamin D3 is available through diet, supplements and exposure of the skin to sunlight, or ultraviolet B (UVB). In the paper, the researchers underscored the importance of limiting sun exposure such that the skin does not change color (tan) or burn. For a typical fair-skinned Caucasian individual, adequate vitamin D could be photosynthesized safely by spending 10 to 15 minutes in the noontime sun on a clear day with 50 percent of skin area exposed to the sun. Darker skinned individuals may require more time in the sun, such as 25 minutes. For people with photosensitivity disorders, or anyone with a personal or family history of nonmelanoma skin cancer, any amount of extra sun exposure would be inadvisable.
A larger daily dose of vitamin D could reduce the incidence of colorectal cancer with minimal risk, according to a new review that pools results from five studies._
The analysis found that maintaining a specific target blood level of vitamin D was associated with a 50 percent lower risk of colorectal cancer than that seen in people with consistently lower blood levels._
Previous studies had shown that lower blood levels of vitamin D did not protect against colorectal cancer, according to lead author Edward Gorham, Ph.D., a research epidemiologist with the Naval Health Research Center in San Diego. However, a meta-analysis pools the data from several studies, thus increasing the strength of the results._
The study is being published in the March issue of the American Journal of Preventive Medicine._
The five studies looked at serum collected from healthy volunteers who were then followed for periods ranging from two years to 25 years. There were 535 cases in the pooled analysis and 913 controls, or 1,448 total participants._
The researchers found that a blood serum vitamin D level of 33 nanograms per milliliter or higher was associated with a 50 percent lower risk of colorectal cancer than that seen with blood levels of 12 nanograms per milliliter or lower.
Vitamin D levels in the body are a factor of both diet and sun exposure. Exposing the skin to the sun lets the body synthesize vitamin D, which is why mortality due to colorectal cancer may be higher in geographic areas that get less sunshine._
The amount of dietary vitamin D needed to reach the serum levels that appear to be protective against colorectal cancer — 1,000 to 2,000 international units a day — would not pose any risk, according to Gorham: “The Institute of Medicine has set a ‘No Adverse Effect Level’ of 2,000 IU per day for vitamin D intake, so this recommendation would be safe for most people.”
There is no official recommended dietary allowance for vitamin D, but an adequate dietary intake per day for most adults is currently considered to be 200 to 400 IU._
Small amounts of sun exposure would also help people boost their vitamin D levels. Fifteen to 20 minutes per day without sunscreen is enough for the body to synthesize 10,000 IU of vitamin D with minimal risk of sunburn or skin cancer, Gorham said.
“The results are pretty straightforward,” said Karen Glanz, Ph.D., director of Emory University’s Prevention Research Center at the Rollins School of Public Health. However, changing behavior on the basis of this study may be premature, she said. The analysis found an association between vitamin D levels and lowered risk, not a definite link, Glanz said, but adding vitamin D to the diet or taking a supplement would probably not do much harm and there could be a benefit.__The meta-analysis on colorectal cancer includes data from the Women's Health Initiative, which had shown in 2006 that a low dose of vitamin D did not protect against colorectal cancer within seven years of follow-up. However, the researchers wrote, the meta-analysis indicates that a higher dose may reduce its incidence.__"Meta-analysis is an important tool for revealing trends that may not be apparent in a single study," said co-author Sharif B. Mohr, M.P.H. "Pooling of independent but similar studies increases precision, and therefore the confidence level of the findings."
Winter Sun Makes It Difficult to Get Vitamin D Naturally
As the days grow shorter, the sun’s warm rays aren’t the only thing your body may be missing, warns Creighton University researcher Joan Lappe, Ph.D.
If you live in North American at latitudes above the 37th parallel – Omaha is near the 41st parallel - you also may not be getting enough vitamin D, says Lappe, professor of medicine and holder of the Criss/Beirne Endowed Chair in the Creighton School of Nursing.
And that vitamin D is important to your health. In fact, a landmark study by Lappe and other Creighton researchers, published in June in the American Journal of Clinical Nutrition, showed a direct link between vitamin D and cancer prevention._Humans can get vitamin D from several sources.
During the summer, the body can convert solar energy into ample amounts of vitamin D with just 10-15 minutes exposure daily to the sun. That’s not possible this time of year.
“From October until the end of March, the angle of the sun is such that, in much of North America, no vitamin D is available from that source,” Lappe says. “What that means is most of us are deficient in vitamin D this time of year.”
While you can get the vitamin from fish oil and a few fortified foods, it’s difficult to take in adequate amounts of vitamin D by eating alone. Lappe recommends taking vitamin D3 – the same form of the vitamin that humans make from exposure to the sun.
The amount of vitamin D you should take daily is a subject of great debate, Lappe notes.
The U.S. government’s recommended daily allowance is 200 IU until age 50, 400 IU for 50-70 year olds, and 600 IU after age 70. However, many medical experts believe those recommendations are way too low.
The Canadian Cancer Society recently recommended that people with light skin take 1,000 IU of the vitamin supplement during fall and winter, while people with darker skin or limited sun exposure take that amount throughout the year.
The society’s recommendation coincided with the publication of the Creighton (Cray-ton) research in June. The four-year study involving 1,179 Nebraska women showed that women taking calcium supplements plus 1,100 IU of vitamin D3 daily, experienced a 60 percent decrease in their risk of developing cancer than a placebo group.
“Generally, medical experts consider it safe to take between 1,000 IU and 2,000 IU of vitamin D supplements daily,” Lappe says.
Vitamin D Reduces Cancer Risk - Sun Not Enough
Most Americans and others are not taking enough vitamin D, a fact that may put them at significant risk for developing cancer, according to a landmark study conducted by Creighton University School of Medicine.
The four-year, randomized study followed 1,179 healthy, postmenopausal women from rural eastern Nebraska.* Participants taking calcium, as well as a quantity of vitamin D3 nearly three times the U.S. government’s Recommended Daily Amount (RDA) for middle-age adults, showed a dramatic 60 percent or greater reduction in cancer risk than women who did not get the vitamin.
The results of the study, conducted between 2000 and 2005, were reported in the June 8 online edition of the American Journal of Clinical Nutrition.
“The findings are very exciting. They confirm what a number of vitamin D proponents have suspected for some time but that, until now, have not been substantiated through clinical trial,” said principal investigator Joan Lappe, Ph.D., R.N., Creighton professor of medicine and holder of the Criss/Beirne Endowed Chair in the School of Nursing. “Vitamin D is a critical tool in fighting cancer as well as many other diseases.”
Research participants were all 55 years and older and free of known cancers for at least 10 years prior to entering the Creighton study. Subjects were randomly assigned to take daily dosages of 1,400-1,500 mg supplemental calcium, 1,400-1,500 mg supplemental calcium plus 1,100 IU of vitamin D3, or placebos. National Institutes of Health funded the study.
Over the course of four years, women in the calcium/vitamin D3 group experienced a 60 percent decrease in their cancer risk than the group taking placebos.
On the premise that some women entered the study with undiagnosed cancers, researchers then eliminated the first-year results and looked at the last three years of the study. When they did that, the results became even more dramatic with the calcium/vitamin D3 group showing a startling 77 percent cancer-risk reduction.
In the three-year analysis, there was no statistically significant difference in cancer incidence between participants taking placebos and those taking just calcium supplements.
Through the course of the study, 50 participants developed nonskin cancers, including breast, colon, lung and other cancers.
Lappe said further studies are needed to determine whether the Creighton research results apply to other populations, including men, women of all ages, and different ethnic groups. While the study was open to all ethnic groups, all participants were Caucasian, she noted.
There is a growing body of evidence that a higher intake of vitamin D may be helpful in the prevention and treatment of cancer, high blood pressure, fibromyalgia, diabetes mellitus, multiple sclerosis, and rheumatoid arthritis and other diseases.
Humans make their own vitamin D3 when they are exposed to sunlight. In fact, only 10-15 minutes a day in a bright summer sun creates large amounts of the vitamin, Lappe said. However, people need to exercise caution since the sun’s ultraviolet B rays also can cause skin cancer; sunscreen blocks most vitamin D production.
In addition, the latitude at which you live and your ancestry also influence your body’s ability to convert sunlight into vitamin D. People with dark skin have more difficulty making the vitamin. Persons living at latitudes north of the 37th parallel – Omaha is near the 41st parallel – cannot get their vitamin D naturally during the winter months because of the sun’s angle.
Experts generally agree that the RDA** for vitamin D needs to be increased substantially, however there is debate about the amount. Supplements are available in two forms – vitamin D2 and vitamin D3. Creighton researchers recommend vitamin D3 , because it is more active and thus more effective in humans.
It’s not yet clear why overweight elderly adults have low levels of vitamin D in their blood. However, researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (USDA HNRCA) have found that lack of sun exposure may not account for low levels of vitamin D in elders who are overweight.
“People aged 65 and over with high percent body fat have lower levels of 25-hydroxyvitamin D, the storage form of vitamin D, compared to those who have lower percent body fat,” says corresponding author Susan Harris, DSc, epidemiologist in the Bone Metabolism Laboratory at the USDA HNRCA.
Harris and co-author Bess Dawson-Hughes, MD, director of the Bone Metabolism Laboratory at the USDA HNRCA, interviewed 381 Caucasian men and women aged 65 and over about their sun exposure over a previous three-month period.
Individuals reported how much time they spent outdoors, how much skin was exposed while outdoors, and whether or not they wore sunscreen. Seasonality, or when the individual entered the study, was also taken into account, because in Boston, where the study was conducted, sun rays are weak in winter compared with summer months. The researchers measured participants’ percent body fat using dual-energy x-ray absorptiometry (DXA), a precise method for determining body composition. Individuals were grouped into quartiles of percent body fat: less than 28 percent, 28 percent to 33 percent, 34 percent to 40 percent, and greater than 40 percent. Blood levels of 25-hydroxyvitamin D were measured and participants were asked to fill out a dietary questionnaire to measure the amount of vitamin D they obtained from food.
Harris and Dawson-Hughes found that when adjusted for sex, age, seasonality and dietary vitamin D intake, 25-hydroxyvitamin D significantly decreased as body fat increased, (P<0.024). When the researchers further adjusted for sunlight exposure variables, 25-hydroxyvitamin D values still significantly decreased as body fat increased. “Sunlight exposure could not account for low vitamin D stores in older people with high percent body fat,” explains Harris.
Vitamin D is called the “sunshine vitamin” because it is produced by the body when the skin is exposed to ultraviolet (UV) rays from the sun. Vitamin D can also be obtained from foods such as fish and fortified milk and from supplements. When this fat-soluble vitamin enters the body it is converted in the liver to 25-hydroxyvitamin D. This is one of several important forms of vitamin D, and is the form that researchers and clinicians use as an indicator of vitamin D status in individuals. “Vitamin D is especially critical in maintaining bone health, and there is evidence that many older Americans have low blood levels of vitamin D, which can put them at risk for bone fractures and osteoporosis,” says Dawson-Hughes, who is also a professor at Tufts University School of Medicine.
“These results cannot be carried over to other populations, such as young people, or elderly living in different climates. However, if low vitamin D stores are not attributed to low sunlight exposure in this population, it suggests that we should explore other possibilities,” says Harris. “The most likely explanation seems to be that vitamin D is sequestered in fat tissue, reducing its entry into the blood.”
Study shines more light on benefit of vitamin D in fighting cancer
600,000 cases a year of breast and colorectal cancer could be prevented each year by adequate intake of vitamin D, according to researcher
A new study looking at the relationship between vitamin D serum levels and the risk of colon and breast cancer across the globe has estimated the number of cases of cancer that could be prevented each year if vitamin D3 levels met the target proposed by researchers.
Cedric F. Garland, Dr.P.H., cancer prevention specialist at the Moores Cancer Center at the University of California, San Diego (UCSD) and colleagues estimate that 250,000 cases of colorectal cancer and 350,000 cases of breast cancer could be prevented worldwide by increasing intake of vitamin D3, particularly in countries north of the equator. Vitamin D3 is available through diet, supplements and exposure of the skin to sunlight.
“For the first time, we are saying that 600,000 cases of breast and colorectal cancer could be prevented each year worldwide, including nearly 150,000 in the United States alone,” said study co-author Garland. The paper, which looks at the dose-response relationship between vitamin D and cancer, will be published in the August edition of the journal Nutrition Reviews.
The study combined data from surveys of serum vitamin D levels during winter from 15 countries. It is the first such study to look at satellite measurements of sunshine and cloud cover in countries where actual blood serum levels of vitamin D3 had also been determined. The data were then applied to 177 countries to estimate the average serum level of a vitamin D metabolite of people living there.
The data revealed an inverse association of serum vitamin D with risk of colorectal and breast cancer. The protective effect began at levels ranging from 24 to 32 nanograms per milliliter of 25-hydroxyvitamin D concentration in the serum. The 25-hydroxyvitamin D level is the main indicator of vitamin D status. The late winter average 25-hydroxyvitamin D in the US is about 15-18 ng/ml. The researchers maintain that increasing vitamin D levels in populations, particularly those in northern climates, has the potential to both prevent and possibly serve as an adjunct to existing treatments for cancer.
The work builds on previous studies by Garland and colleagues (Journal of Steroid Biochemistry and Molecular, February 2007) which found that raising the serum 25(OH)D levels to 55 ng/mL was optimal for cancer prevention. This is the first study to recommend optimal vitamin D serum levels which, Garland said, are high enough to provide the needed benefit but which have been found by other scientists to be low enough to avoid health risks.
“This could be best achieved with a combination of diet, supplements and short intervals – 10 or 15 minutes a day – in the sun,” said Garland. It could be less for very fair-skinned individuals. He went on to say that “the appropriate dose of vitamin D in order to reach this level, could be very little in a lifeguard in Southern California… or quite a lot for someone in Northern Europe who tends to remain indoors most of the year.”
The serum level recommended by the study would correspond to intake of 2000 International Units per day of vitamin D3 for a meaningful reduction in colorectal cancer. The researchers recommend 2000 IU/day, plus, when weather allows, a few minutes in the sun with at least 40% of the skin exposed, for a meaningful reduction in breast cancer incidence, unless the individual has a history of skin cancer or a photosensitivity disease.
Garland also recommends moderate sun exposure and use of clothing and a hat when in the sun longer than 15 minutes.
This paper used worldwide data only recently available through a new tool called GLOBOCAN, developed by the World Health Organization’s International Agency for Research on Cancer. GLOBOCAN is a database of cancer incidence, mortality and prevalence for 177 countries. Previous studies from this core group have shown an association between higher levels of vitamin D3 or markers of vitamin D status and lower risk of cancers of the breast, colon, ovary and kidney. The researchers underscore their call for prompt public health action to increase intake of vitamin D3 as an inexpensive tool for prevention of diseases that claim nearly one million lives each year world wide.
“The message is, depending on where you live, you may need to consider taking in considerably higher levels of vitamin D3 than those currently recommended,” said Garland. “I’d recommend discussing vitamin D needs with a health care professional, who may order and interpret a simple blood test for a vitamin D metabolite [25(OH)D], and provide a dosage recommendation that’s appropriate for the individual’s needs.”
Vitamin D and breast cancer risk
A connection between vitamin D level and the risk of developing breast cancer has been implicated for a long time, but its clinical relevance had not yet been proven. Sascha Abbas and colleagues from the working group headed by Dr. Jenny Chang-Claude at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), collaborating with researchers of the University Hospitals in Hamburg-Eppendorf, have now obtained clear results: While previous studies had concentrated chiefly on nutritional vitamin D, the researchers have now investigated the complete vitamin D status. To this end, they studied 25-hydroxyvitamin D (25(OH)D) as a marker for both endogenous vitamin D and vitamin D from food intake.
The result of the study involving 1,394 breast cancer patients and an equal number of healthy women after menopause was surprisingly clear: Women with a very low blood level of 25(OH)D have a considerably increased breast cancer risk. The effect was found to be strongest in women who were not taking hormones for relief of menopausal symptoms. However, the authors note that, in this retrospective study, diagnosis-related factors such as chemotherapy or lack of sunlight after prolonged hospital stays might have contributed to low vitamin levels of breast cancer patients.
In addition, the investigators focused on the vitamin D receptor. The gene of this receptor is found in several variants known as polymorphisms. The research team of the DKFZ and Eppendorf Hospitals investigated the effect of four of these polymorphisms on the risk of developing breast cancer. They found out that carriers of the Taql polymorphism have a slightly increased risk of breast tumors that carry receptors for the female sex hormone estrogen on their surface. No effects on the overall breast cancer risk were found. A possible explanation offered by the authors is that vitamin D can exert its cancer-preventing effect by counteracting the growth-promoting effect of estrogens.
Besides its cancer-preventing influence with effects on cell growth, cell differentiation and programmed cell death (apoptosis), vitamin D regulates, above all, the calcium metabolism in our body. Foods that are particularly rich in vitamin D include seafish (cod liver oil), eggs and dairy products. However, the largest portion of vitamin D is produced by our own body with the aid of sunlight.
itamin D in brain function
Vitamin D supplementation for high risk groups may be warranted
In a definitive critical review, scientists at Children’s Hospital & Research Center Oakland ask whether there is convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction. Joyce C. McCann, Ph.D., assistant staff scientist and Bruce N. Ames, Ph.D., senior scientist at Children’s Hospital Oakland Research Institute (CHORI) conclude that there is ample biological evidence to suggest an important role for vitamin D in brain development and function, and that supplementation for groups chronically low in vitamin D is warranted. Their conclusions will be published on April 22, 2008 in the Federation of American Societies for Experimental Biology (FASEB) Journal.
“This critical analysis of vitamin D function and the brain is a model of careful thinking about nutrition and behavior”, says Gerald Weissmann, MD, Editor-in-Chief of the FASEB Journal “One wishes that all studies of nutritional supplements or requirements were this thoughtful. Drs. McCann and Ames deftly show that while vitamin D has an important role in the development and function of the brain, its exact effects on behavior remain unclear. Pointing to the need for further study, the authors argue for vitamin D supplementation in groups at risk.”
Vitamin D has long been known to promote healthy bones by regulating calcium levels in the body. Lack of sufficient vitamin D in very young children results in rickets, which can be easily prevented by vitamin D supplements. Only recently the scientific community has become aware of a much broader role for vitamin D. For example, we now know that, in addition to its role in maintaining bone health, vitamin D is involved in differentiation of tissues during development and in proper functioning of the immune system. In fact, over 900 different genes are now known to be able to bind the vitamin D receptor, through which vitamin D mediates its effects. In addition to protecting against rickets, evidence now strongly indicates that a plentiful supply of vitamin D helps to protect against bone fractures in the elderly. Evidence also continues to accumulate suggesting a beneficial role for vitamin D in protecting against autoimmune diseases, including multiple sclerosis and type I diabetes, as well as some forms of cancer, particularly colorectal and breast.
Vitamin D is present in only a few foods (e.g., fatty fish), and is also added to fortified milk, but our supply typically comes mostly from exposure to ultraviolet rays (UV) in sunlight. UV from the sun converts a biochemical in the skin to vitamin D, which is then metabolized to calcitriol, its active form and an important hormone. Formation of vitamin D by UV can be 6 times more efficient in light skin than dark skin, which is an important cause of the known widespread vitamin D deficiency among African Americans living in northern latitudes. Dark skin has been selected during evolution because it protects against the burning UV rays of the sun in the tropics. White skin has been selected for allowing as much UV exposure to make sufficient vitamin D in Northern (high) latitudes. Thus, fair-skinned northerners are at risk in Australia or Arizona for sunburns and UV-induced cancer, while dark-skinned people in the Northern U.S. or European latitudes with little exposure to the sun are at risk for rickets, bone fractures and possibly other diseases including several types of cancer due to a lack of vitamin D. Fortunately sun-screens and vitamin D supplements are inexpensive.
McCann & Ames point out that evidence for vitamin D’s involvement in brain function includes the wide distribution of vitamin D receptors throughout the brain. They also discuss vitamin D’s ability to affect proteins in the brain known to be directly involved in learning and memory, motor control, and possibly even maternal and social behavior. The review also discusses studies in both humans and animals that present suggestive though not definitive evidence of cognitive or behavioral consequences of vitamin D inadequacy. The authors discuss possible reasons for the apparent discrepancy between the biological and behavioral evidence, and suggest new, possibly clarifying avenues of research.
Many vitamin D experts advise that the currently recommended level of vitamin D intake is much too low and should be raised to protect against bone fractures and possibly cancer in addition to rickets (2). Indeed, even using present guidelines, too many Americans have low vitamin D blood levels. McCann & Ames propose that, despite uncertainty regarding all of the deleterious effects of vitamin D inadequacy, the evidence overall indicates that supplementation, which is both inexpensive and prudent, is warranted for groups whose vitamin D status is exceptionally low, particularly nursing infants, the elderly, and African Americans (e.g., see (3)).
This review is the fourth in a series by McCann & Ames that critically evaluate scientific evidence linking deficiencies in micronutrients (the approximately 40 vitamins, minerals, amino acids, and fatty acids required for the body to function) to brain function. Other reviews in the series discuss the long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) (4, 5), choline (6), and iron (7).
Could vitamin D, a key milk nutrient, affect how you age?
New study suggests boosting vitamin D may have long-term benefits for inflammation, aging
WASHINGTON, D.C. (November 8, 2007)- There is a new reason for the 76 million baby boomers to grab a glass of milk. Vitamin D, a key nutrient in milk, could have aging benefits linked to reduced inflammation, according to a new study published in the American Journal of Clinical Nutrition.
In a genetic study of more than 2,100 female twin pairs ages 19-79, British and American researchers found that higher vitamin D levels were linked to improved genetic measures of lifelong aging and chronic stress. Using a genetic marker called leukocyte telomere length (LTL), they found those with the highest vitamin D levels had longer LTL, indicating lower levels of inflammation and body stress. The telomere difference between those with the highest and lowest vitamin D levels was equivalent to 5 years of aging.
Previous research has found that shortened LTL is linked to risk for heart disease and could be an indication of chronic inflammation – a key determinant in the biology of aging. While there are several lifestyle factors that affect telomere length (obesity, smoking and lack of physical activity), the researchers noted that boosting vitamin D levels is a simple change to affect this important marker.
Studies continue to link vitamin D to an array of health benefits, securing vitamin D’s “super nutrient” status and providing even more reasons to get adequate amounts of this essential vitamin. Recent research suggests that beyond its well-established role in bone health, vitamin D also may help reduce the risk of certain cancers and autoimmune diseases, such as type 1 diabetes, rheumatoid arthritis and multiple sclerosis.
Milk is a primary source of calcium and vitamin D in the American diet. In fact, government reports indicate that more than 70 percent of the calcium in our nation’s food supply comes from milk and milk products. Additionally, milk is one of the few food sources of vitamin D, which is fast emerging as a “super nutrient.”
The recommended three servings of low fat or fat-free milk provides 900 mg of calcium, 300 IU of vitamin D and 80 mg of magnesium daily.
Study finds no connection between vitamin D and overall cancer deaths
No relationship was found between vitamin D levels and the overall risk of dying from cancer, according to a study published online October 30 in the Journal of the National Cancer Institute. However, higher vitamin D levels were associated with a decreased risk of colorectal cancer death.
Several epidemiological studies have supported the hypothesis that that vitamin D can reduce cancer mortality by decreasing cancer incidence or improving survival. Animal and cell studies suggest that vitamin D may reduce tumor growth and induce cancer cell death. Diet and exposure to sunlight are the major sources of vitamin D.
D. Michal Freedman, Ph.D., of the National Cancer Institute in Bethesda, Md., and colleagues analyzed data from the third national Health and Nutrition Examination Survey to examine the relationship between levels of circulating vitamin D in the blood and cancer mortality in a group of 16,818 participants aged 17 and older.
After about a decade of follow-up, 536 participants had died of cancer. Cancer mortality was not related to the level of circulating vitamin D for the overall group, nor was it related when the researchers looked at the data by sex, race, or age. But higher levels of vitamin D (80 nmol/L or more) were associated with a 72 percent reduced risk of colorectal cancer mortality, compared with lower levels (less than 50 nmol/L).
“To our knowledge, this study is the first to examine the relationship between measured serum vitamin D levels and cancer mortality for selected site and for all sites combined,” the authors write.
In an accompanying editorial, Cindy Davis, Ph.D., and Johanna Dwyer, D.Sc. of the National Institutes of Health in Bethesda, Md., discuss the complicated relationship between nutrients, like vitamin D, and cancer. They suggest that not enough is known about the benefits and limitations of vitamin D to use it for the prevention of disease or death.
“These findings must be put into the context of total diet and lifestyle. There are many risk factors other than diet for colorectal cancer, and there are many possible dietary risk factors other than vitamin D that have been linked to cancer risk,” the editorialists write.
Vitamin D deficiency: Common and problematic yet preventable
In a review article to appear in the July 19th issue of the New England Journal of Medicine, Dr. Michael Holick, an internationally recognized expert in vitamin D, provides an overview of his pioneering work that expounds on the important role vitamin D plays in a wide variety of chronic health conditions, as well as suggesting strategies for the prevention and treatment of vitamin D deficiency.
Humans attain vitamin D from exposure to sunlight, diet and supplements. Vitamin D deficiency is common in children and adults. In utero and childhood, vitamin D deficiency may cause growth retardation, skeletal deformities and increase risk of hip fractures later in life. In adults, vitamin D deficiency may precipitate or exacerbate osteopenia, osteoporosis, muscle weakness, fractures, common cancers, autoimmune diseases, infectious diseases and cardiovascular diseases.
According to Holick, a professor of medicine, physiology, and biophysics, and director of the General Clinical Research Center at Boston University School of Medicine and Director of the Bone Healthcare Clinic at Boston Medical Center, it has been estimated that 1 billion people world-wide are vitamin D deficient or insufficient.
Without vitamin D only about 10-15 percent of dietary calcium and about 60 percent of phosphorus is absorbed by the body. This is directly related to bone mineral density which is responsible for osteoporosis and fractures, as well as muscle strength and falls in adults. In utero and childhood, calcium and vitamin D deficiency prevents the maximum deposition of calcium in the skeleton.
Studies have shown people living at higher latitudes (where the angle of the sun’s rays are unable to sufficiently produce adequate amounts of vitamin D in the skin) are more likely to develop and die of Hodgkin’s lymphoma, colon, pancreatic, prostate, ovarian, breast and other cancers. According to Holick, both prospective and retrospective epidemiologic studies have also shown an association between low levels of vitamin D and an increased risk for Type 1 diabetes, multiple sclerosis, Crohn’s disease, hypertension and cardiovascular disease.
Holick believes the current recommended Adequate Intakes for vitamin D need to be increased to 800 – 1000 IU vitaminD3/d. “However, one can not obtain these amounts from most dietary sources unless one is eating oily fish frequently,” says Holick. “Thus, sensible sun exposure (or UVB irradiation) and/or supplements are required to satisfy the body’s vitamin D requirement,” he adds.
Lastly Holick adds, “The goal of this paper is to make physicians aware of the medical problems associated with vitamin D deficiency. Physicians will then be able to impart this knowledge to their patients so they too will know how to recognize, treat and most importantly, maintain adequate levels of this important vitamin.”
Low Vitamin D = Poor Physical Performance
Older adults who don’t get enough vitamin D – either from their diets or exposure to the sun – may be at increased risk for poor physical performance and disability, according to new research from Wake Forest University School of Medicine and colleagues.__“With a growing older population, we need to identify better ways to reduce the risk of disability,” said lead author Denise Houston, Ph.D. “Our study showed a significant relationship between low vitamin D levels in older adults and poorer physical performance.”__The results are reported in the April issue of the Journal of Gerontology: Medical Sciences.__About one-fourth of people over age 60 have low vitamin D levels. Previous research has shown that vitamin D not only plays a role in bone health, but possibly also in protecting against diabetes, cancer, colds and tuberculosis.__“Recent findings showing the importance of vitamin D status on multiple health outcomes underscore the need for more research on the effects of low vitamin D levels in elderly populations,” said Houston, an instructor in internal medicine - gerontology.__Vitamin D is naturally produced when skin is exposed to the sun’s ultraviolet rays. Foods such as fortified milk, juice and cereals also contain vitamin D, but it is difficult to get enough through diet alone, said Houston.__Older adults are particularly prone to low vitamin D levels because they may get less exposure to sunlight and because their skin is less efficient in producing vitamin D from sun exposure compared to younger adults. Older adults also may not get enough vitamin D from dietary sources.__“There is a growing awareness that the prevalence of low vitamin D levels is common among the elderly,” said Houston.__For the current study, researchers analyzed data from the InCHIANTI study, which evaluated factors contributing to the decline of mobility in late life. The study involved 976 people who were 65 years and older from two towns in the Chianti area of Italy. The mean age of participants was 74.8 years. Data were collected from Sept. 1998 through March 2000.__Participants completed a short physical performance test of their walking speed, ability to stand from a chair and ability to maintain their balance in progressively more challenging positions. In addition, handgrip strength, a predictor of future disability, was measured using a hand-held dynamometer.__The researchers found that physical performance and grip strength were about five to 10 percent lower in those who had low levels of vitamin D. After looking at other variables that could influence the results, such as body mass index, physical activity, the season of the year, mental abilities, health conditions and anemia, the results held true.__The study wasn’t designed to evaluate whether low vitamin D levels actually cause poor physical performance, but the results suggest the need for additional research in this area, said Houston. She said vitamin D plays an important role in muscle function, so it is plausible that low levels of the vitamin could result in lower muscle strength and physical performance.__“But it’s also possible that those with poor physical performance had less exposure to sunlight resulting in low vitamin D levels,” she said.__Current recommendations call for people from age 50 to 69 to get 400 international units (IUs) of vitamin D per day and for those over age 70 to get 600 IUs. Many researchers, however, suggest that higher amounts may be needed.__“Higher amounts of vitamin D may be needed for the preservation of muscle strength and physical function as well as other conditions such as cancer prevention,” said Houston. “The current recommendations are based primarily on vitamin D’s effects on bone health.”__Also see "new-studies-back-vitamin-d-for-cancer prevention":_http://healthnewsreport.blogspot.com/2007/02/2-new-studies-back-vitamin-d-for-cancer.html
Vitamin D supplements appear to be associated with lower risk of death
Individuals who take vitamin D supplements appear to have a lower risk of death from any cause over an average follow-up time of six-years, according to a meta-analysis of 18 previously published studies in the September 10 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Past studies have suggested that deficiencies in vitamin D might be associated with a higher risk of death from cancer, heart disease and diabetes—illnesses that account for 60 percent to 70 percent of deaths in high-income nations, according to background information in the article. “If the associations made between vitamin D and these conditions were consistent, then interventions effectively strengthening vitamin D status should result in reduced total mortality,” the authors write.
Philippe Autier, M.D., of the International Agency for Research on Cancer, Lyon, France, and Sara Gandini, Ph.D., of the European Institute of Oncology, Milano, Italy, searched for randomized controlled trials of vitamin D supplements published before November 2006. They analyzed 18 separate trials that included 57,311 participants and evaluated doses of vitamin D ranging from 300 to 2,000 international units, with an average dose of 528 international units. Most commercially available supplements contain between 400 and 600 international units.
Over an average follow-up period of 5.7 years, 4,777 of the participants died. Individuals who took vitamin D had a 7 percent lower risk of death than those who did not. In the nine trials that collected blood samples, those who took supplements had an average 1.4- to 5.2-fold higher blood level of vitamin D than those who did not.
“Mechanisms by which vitamin D supplementation would decrease all-cause mortality are not clear,” the authors write. Vitamin D could inhibit some mechanisms by which cancer cells proliferate, or it may boost the function of blood vessels or the immune system, they note.
“In conclusion, the intake of ordinary doses of vitamin D supplements seems to be associated with decreases in total mortality rates,” the authors write. “The relationship between baseline vitamin D status, dose of vitamin D supplements and total mortality rates remains to be investigated. Population-based, placebo-controlled randomized trials in people 50 years or older for at least six years with total mortality as the main end point should be organized to confirm these findings.”
Vitamin D Inadequacy May Exacerbate Chronic Pain
Approximately one in four patients who suffer from chronic pain also have inadequate blood levels of vitamin D, possibly contributing to their ongoing pain, according to a new study. Patients lacking sufficient vitamin D also required higher doses of morphine for a longer period of time.
Researchers recorded the serum vitamin D levels of 267 adults undergoing outpatient treatment for chronic pain, as well as their pain medication (morphine) dose and duration of use, and physical and general health functioning.
Of the patients tested, 26 percent had vitamin D inadequacy. Among these patients, the morphine dose was nearly twice that of the group with adequate vitamin D levels. In addition, the vitamin D inadequacy group used morphine for an average of 71.1 months versus 43.8 months. The vitamin D deficient group also reported lower levels of physical functioning and had a poorer view of their overall health.
It has long been known that inadequate levels of vitamin D can cause pain and muscle weakness, according to the study author, W. Michael Hooten, M.D., medical director, and anesthesiologist at Mayo Comprehensive Pain Rehabilitation Center, Rochester, Minnesota. Previous studies also have suggested that pain-related symptoms of vitamin D inadequacy respond poorly to pain medications.
However, “this is the first time that we have established the prevalence of vitamin D inadequacy among a diverse group of chronic pain patients,” Dr. Hooten said.
“The implications are that in chronic pain patients, vitamin D inadequacy is not the principal cause of pain and muscle weakness, however, it could be a contributing but unrecognized factor,” Dr. Hooten said.
Vitamin D inadequacy can be “easily and inexpensively” treated “with essentially no side effects” using a prescription supplement, once or twice a week for four to six weeks, Dr. Hooten said. Further study is needed to determine whether treating inadequate vitamin D levels will result in improvements to the overall general health for patients with chronic pain.
Vitamin D protects cells from stress that can lead to cancer
By inducing a specific gene to increase expression of a key enzyme, vitamin D protects healthy prostate cells from the damage and injuries that can lead to cancer, University of Rochester Medical Center researchers report.
“Many epidemiological studies have suggested the beneficial properties of vitamin D,” said Yi-Fen Lee, associate professor of urology at the Medical Center who led the research. “Our findings reflect what we see in those studies and demonstrate that vitamin D not only can be used as a therapy for prostate cancer, it can prevent prostate cancer from happening.”
The International Journal of Cancer published the findings in its June 15 issue.
Lee and her research team discovered one mechanism involving vitamin D that protects cells from oxidative stress. The vitamin D used in the study is 1,25-hydroxylvitamin D3, the most potent and active form of vitamin D in the human body. Nonmalignant human prostate epithelial cells also were used.
Normal metabolism in cells generates reactive oxygen species (ROS), molecules of peroxide, for example, or so-called free radicals. These substances can play a role in cell signaling and even kill bacteria. Exposure to some chemicals or forms of radiation can produce high levels of ROS that can damage DNA and play a significant role in speeding aging or causing cancer.
Lee found that vitamin D links with a gene known as G6PD, increasing its activity and the production of an enzyme called glucose-6-phosphate dehydrogenase. Increased activity of the enzyme clears cells of ROS, the molecules that can damage and injure cells.
“If you reduce DNA damage, you reduce the risk of cancer or aging,” Lee said. “Our study adds one more beneficial effect of taking a vitamin D supplement. Taking a supplement is especially important for senior citizens and others who might have less circulation of vitamin D, and for people who live and work areas where there is less sunshine.”
Einstein researchers find that vitamin D may protect against peripheral artery disease
(BRONX, NY) – People with low vitamin D levels may face an increased risk for peripheral artery disease (PAD), according to researchers at the Albert Einstein College of Medicine of Yeshiva University. The scientists reported their findings at the American Heart Association’s Arteriosclerosis, Thrombosis and Vascular Biology Annual Conference 2008.
PAD is a common disease that occurs when arteries in the legs become narrowed by fatty deposits, causing pain and numbness and impairing the ability to walk. PAD affects about eight million Americans and is associated with significant disease and death, according to the American Heart Association.
People obtain vitamin D by making it themselves (through skin exposure to sunlight), by ingesting foods such as fish and fortified dairy products that contain vitamin D, or by taking dietary supplements. Adequate vitamin D levels are necessary for bone health, but scientists are only beginning to explore vitamin D’s connection to cardiovascular disease.
“We know that in mice, vitamin D regulates one of the hormone systems that affects blood pressure,” said Dr. Michal Melamed, lead author of the study and assistant professor in the departments of Medicine and Epidemiology & Population Health at Einstein. “Since cells in the blood vessels have receptors for vitamin D, it may directly affect the vessels, although this has not been fully worked out.”
To see whether vitamin D might influence PAD, Dr. Melamed and colleagues analyzed data from a national survey measuring vitamin D levels in the blood of 4,839 U.S. adults. The survey tested these people using the ankle-brachial index, a screening tool for PAD that measures blood flow to the legs. Also measured were other risk factors for PAD such as cholesterol levels, blood pressure and presence of diabetes.
The researchers found that higher levels of vitamin D were associated with a lower prevalence of PAD. Among individuals with the highest vitamin D levels —more than 29.2 nanogram per milliliter (ng/mL) — only 3.7 percent had PAD. Among those with the lowest vitamin D levels — less than 17.8 ng/mL — 8.1 percent had PAD.
When the researchers adjusted for age, sex, race and co-existing health problems, they found that PAD was 64 percent more common in the group with the lowest vitamin D levels compared with the group with the highest levels. For each 10 ng/mL drop in vitamin D level, the risk for PAD increased by 29 percent.
While these findings suggest a role for vitamin D in preventing PAD, Dr. Melamed cautions that they don’t necessarily show that vitamin D truly deserves the credit. It’s possible, she says, that vitamin D levels are a marker for other health practices such as eating a healthy diet. She notes that proving a cause-and-effect relationship between vitamin D and protection against PAD will require a large randomized clinical trial in which some people receive vitamin D supplementation while others do not.
Low Vitamin D Levels Despite Sun Exposure
Vitamin D is often called the “sunshine vitamin” because it is naturally produced by the body when exposed to the Sun’s ultraviolet rays. A new study suggests, however, that even people who receive abundant Sun exposure (nearly 30 hours per week) may still suffer from low serum levels of vitamin D. The researchers measured a form of vitamin D known as 25-hydroxyvitamin, commonly written as 25(OH)D.
“Low vitamin D status is very common and can contribute to the development of osteoporosis and rickets,” said Dr. Neil Binkley of the University of Wisconsin Osteoporosis Clinical Research Program, Madison, and principal author of the study. “Low levels of vitamin D may also play a role in certain cancers, multiple sclerosis, hypertension, and diabetes.”
Researchers conducted a study of 93 adults in Hawaii with self-reported Sun exposure of 28.9 hours per week. Of the 93 participants (30 women and 63 men), 47 (51 percent) had low levels of vitamin D. No correlation was found between serum 25(OH)D and age, lightest or darkest skin color, hours per week of Sun exposure without sunscreen, sun index, total hours of Sun exposure per week, or body mass index (BMI).
The researchers suggest the common clinical recommendation to allow Sun exposure to the hands and face for 15 minutes a day may not assure vitamin D sufficiency.
This paper has been published online and will appear in the June 2007 issue of the Journal of Clinical Endocrinology & Metabolism, a publication of The Endocrine Society.
Aches? Pains? An Extra Dose of Vitamin D May Provide Relief
Pain is the most common complaint leading patients to seek medical care and much of it is chronic, lasting 3 months or longer. According to an extensive review of clinical research in a new report from Pain Treatment Topics, inadequate vitamin D intake has been linked to a long list of chronic painful maladies, including bone and joint pain of various types, muscle pain, fibromyalgia syndrome, rheumatic disorders, osteoarthritis, and other complaints. Lack of vitamin D also has been implicated in the mood disturbances of chronic fatigue syndrome and seasonal affective disorder.
According to Stewart B. Leavitt, MA, PhD, editor of Pain Treatment Topics and author of the report, “our examination of the research, including 22 clinical investigations of patients with various chronic pain and fatigue syndromes, found that these persons almost always had inadequate levels of vitamin D. When sufficient vitamin D supplementation was provided, the aches, pains, weakness, and related problems in most of them either vanished or were at least helped to a significant extent.”
The report, “Vitamin D – A Neglected ‘Analgesic’ for Chronic Musculoskeletal Pain,” was peer-reviewed by a panel of 8 experts and includes the following important points:
>> Vitamin D is a complex nutrient that functions as a hormone to benefit numerous body tissues and organs, including bones, muscles, and nerves.
>> A surprising majority of persons in many parts of the world, including the United States, do not get adequate vitamin D from sun exposure or foods. Why such deficiencies are associated with pain in some persons but not others is not always known.
>> The currently recommended adequate intake of vitamin D – up to 600 IU per day – is outdated and too low. According to the research, most children and adults need at least 1000 IU per day, and persons with chronic musculoskeletal pain would benefit from 2000 IU or more per day of supplemental vitamin D3 (also called cholecalciferol).
>> Vitamin D supplements have a highly favorable safety profile. They interact with very few drugs or other agents, and are usually not harmful unless extremely high doses – such as, 50,000 IU or more – are taken daily for an extended period of time.
>> Vitamin D supplements are easy for patients to self-administer, are well tolerated, and typically cost as little as 7 to 10 cents per day.
Besides the comprehensive *Research Report (50-pages, 170 references), there is available a shorter *Practitioner Briefing (7-pages) that summarizes the report and provides guidance for healthcare providers. Additionally, a special *Patient Brochure (6-pages) explains what vitamin D is, how it works, and how it may help in relieving pain.
*All 3 documents are available for free access at:_http://Pain-Topics.org/VitaminD
In conclusion, Leavitt stresses that vitamin D should not be viewed as a cure for all pain conditions and in all patients. It also is not necessarily a replacement for other pain treatments. “While further research would be helpful,” he says, “current best evidence indicates that recommending supplemental vitamin D for patients with chronic musculoskeletal pain and fatigue disorders would do no harm and could do much good at little cost. It should be considered by healthcare providers for their patients early in the course of pain management.”
Low vitamin D levels associated with death from cardiovascular, all causes
Individuals with lower blood levels of vitamin D appear to have an increased risk of death overall and from cardiovascular causes, according to a report in the June 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
A recent consensus panel estimated that about 50 percent to 60 percent of older individuals in North America and the rest of the world do not have satisfactory vitamin D status, and the situation is similar for younger individuals, according to background information in the article. Blood levels of 25-hydroxyvitamin D, a measure of blood vitamin D levels, lower than 20 to 30 nanograms per milliliter have been associated with falls, fractures, cancer, immune dysfunction, cardiovascular disease and hypertension. These effects are thought to be mediated by the compound 1,25-dihydroxyvitamin D, which is produced by the body and also converted from 25-hydroxyvitamin D.
Harald Dobnig, M.D., of Medical University of Graz, Austria, and colleagues studied 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels in 3,258 consecutive patients (average age 62 years) who were scheduled for coronary angiography testing at a single medical center between 1997 and 2000.
During about 7.7 years of follow-up, 737 (22.6 percent) of participants died, including 463 (62.8 percent) who died of cardiovascular causes. Death rates from any cause and from cardiovascular causes were higher among individuals in the lower one-half of 25-hydroxyvitamin D levels and the lowest one-fourth of 1,25-dihydroxyvitamin D levels. These associations remained when the researchers accounted for other factors, including coronary artery disease, physical activity level and co-occurring diseases.
Low 25-hydroxyvitamin D levels also were correlated with markers of inflammation such as C-reactive protein, as well as signs of oxidative (oxygen-related) damage to cells, the authors note.
"Apart from the proved effects that vitamin D has on bone metabolism and neuromuscular function, appropriate serum levels (that may also be higher than in the present investigation) are associated with a decrease in mortality," they conclude. "Although not proved, it seems possible that at least part of this effect may be due to lowering of a risk profile promoting atherosclerosis [narrowing of the arteries] and preventing cardiovascular end points."
"Based on the findings of this study, a serum 25-hydroxyvitamin D level of 20 nanograms per milliliter or higher may be advised for maintaining general health."
Study Highlights Link Between Vitamin D and Multiple Sclerosis
Vitamin D, the principal regulator of calcium in the body, may prevent the production of malignant cells such as breast and prostate cancer cells and protect against specific autoimmune disorders including multiple sclerosis (MS) according to an article by Sylvia Christakos, PhD, of the UMDNJ-New Jersey Medical School.
In the article, Christakos reports that research shows that the incidence of MS decreases as the amount of vitamin D available to the body increases, either through sunlight exposure or diet. The article notes that MS is “for the most part, unknown in equatorial regions” and that the prevalence of the disease is lower in areas where fish consumption is high. The study is available online in the Journal of Cellular Biochemistry.
“Since vitamin D is produced in the skin through solar or UV irradiation and high serum levels have been shown to correlate with a reduced risk of MS, this suggests that vitamin D may regulate the immune response and may promote a host’s reaction to a pathogen,” Christakos said.
Christakos’ report focuses on the immunosuppressive actions of the active form of vitamin D, which may inhibit the induction of MS, and emphasizes the importance of maintaining a sufficient vitamin D level.
“Evidence has shown that the maintenance of an adequate vitamin D level may have a protective effect in individuals predisposed to MS,” Christakos said. “One device of vitamin D action may be to preserve balance in the T-cell reaction and thus avoid autoimmunity.”
Despite the significant evidence of the benefits of vitamin D relative to MS and other autoimmune diseases, Christakos cautions that further studies are needed to determine whether vitamin D alone or combined with other treatments is effective in individuals with active MS.
Milk nutrients may protect against cancer
New study suggests calcium and vitamin D may reduce cancer risk in women by at least 60 percent
Key milk nutrients, calcium and vitamin D, may do more than just help keep your bones strong. Increasing intake of calcium and vitamin D could reduce the risk for cancer in women by at least 60 percent, according to a new study published in the American Journal of Clinical Nutrition. (1)
The four-year clinical trial included more than one thousand women over the age of 55 in one of three supplement groups: 1) calcium (1400-1500mg) plus vitamin D (1100 IU vitamin D) 2) calcium only (1400-1500 mg) or 3) a placebo. The researchers found that the risk of developing cancer was 60 percent lower for those who took calcium and vitamin D and 47 percent lower for those taking calcium alone, compared to the placebo.
Fifty women developed nonskin cancer through the course of the four-year study, including breast, colon, lung and other cancers. When researchers excluded the 13 cancers diagnosed during first year of the study, determining these cancers were likely present at the study onset, the protective effect of calcium and vitamin D was even greater, with a 77 percent lower risk for cancer for those taking calcium plus vitamin D compared to the placebo.
With an estimated 10.5 million Americans living with cancer, researchers on a quest for new means to prevent or delay the occurrence of this deadly disease are encouraged by these findings.
“This is the first clinical trial to show that boosting vitamin D status can affect the overall risk for cancer – a proposition that has tremendous public health potential,” said lead author Dr Joan Lappe, a nutrition researcher from Creighton University in Omaha. “By choosing vitamin-D rich foods like milk and taking a supplement Americans can help improve their vitamin D levels and potentially impact their cancer risk.”
Milk is the primary source of calcium and an excellent source of vitamin D in the American diet. In fact, government reports indicate that more than 70 percent of the calcium in our nation’s food supply comes from milk and milk products. (2), (3), (4), (5) Additionally, milk is one of the few food sources of vitamin D, which is fast emerging as a “super nutrient.”
Several recent studies have reported similar conclusions, suggesting that calcium and vitamin D may reduce the risk for breast cancer in premenopausal women and colon cancer in older women. (6), (7)Together, these findings give Americans even more reason to meet the recommended three servings of lowfat or fat-free milk each day, providing 900 mg of calcium and 300 IU of vitamin D daily.
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1) Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. American Journal of Clinical Nutrition. 2007;85:1586-1591.
2) Gerrior S, Bente L, Hiza, H. (2004). Nutrient Content of the U.S. Food Supply, 1909-2000. (Home Economics Research Report No. 56). U.S. Department of Agriculture, Center for Nutrition Policy and Promotion.
3) Dietary Guidelines for Americans 2005, U.S. Department of Agriculture, www.healtheirus.gov/dietaryguidelines.
4) Cotton PA, Subar AF, Friday JE, Cook A. Dietary sources of nutrients among US adults, 1994 to 1996. Journal of the American Dietetic Association. 2004; 104:921-930.
5) Weinberg L, Berner LA, Groves JE. Nutrient contributions of dairy foods in the United States, Continuing Survey of Food Intakes by Individuals, 1994-1996, 1998. Journal of the American Dietetic Association. 2004; 104:895-902.
6) Lin J, Manson JE, Lee I, Cook NR, Buring JE, Zhang SM. Intakes of Calcium and Vitamin D and Breast Cancer Risk in Women. Archives of Internal Medicine. 2007;167:1050-1059.
7) Feskanich D, Ma J, Fuchs CS, Kirkner GJ, Hankinson SE, Hollis BW, Giovannucci EL. Plasma vitamin D metabolites and risk of colorectal cancer in women. Cancer Epidemiology Biomarkers and Prevention. 2004;13:1502-1508.
An adequate amount of Vitamin D is known to improve bone density, but the impact goes much further than bone strength; Vitamin D deficiency can impact nearly all of the body’s functions. This topic will be investigated at the American Association of Clinical Endocrinologists (AACE) 17th Annual Meeting & Clinical Congress, on Thursday, May 15, 2008, at the Walt Disney World Dolphin Resort in Orlando.
“Vitamin D plays an important role in most of the body’s tissues,” Robert P. Heaney, FACP, FACN said. “Despite its vast importance in the human body, most people don’t receive enough.”
Vitamin D deficiency can manifest itself in a variety of different forms, depending on a person’s genetic makeup. It can result in impaired bone mineralization, and leads to bone softening diseases like rickets in children and osteomalacia in adults, and is a possible contributor to osteoporosis.
Although many are familiar with the importance of Vitamin D in bones, evidence shows that Vitamin D may be associated with diabetes, hypertension, multiple sclerosis, infectious diseases, and even cancer.
Fight Off Aches & Pains This Winter With Extra Vitamin D
It’s no wonder many people feel achy and sore, and sometimes tired and depressed, during winter months – they’re often not getting enough vitamin D. The body makes vitamin D from the sun’s ultraviolet rays, so it’s known as the sunshine vitamin, but this source is in short supply throughout late fall and winter.
According to an extensive review of clinical research in a report from Pain Treatment Topics (http://Pain-Topics.org), inadequate vitamin D has been linked to a long list of painful maladies, including bone and joint pain, muscle aches, fibromyalgia syndrome, rheumatic disorders, osteoarthritis, and other complaints. Lack of vitamin D also has been implicated in the mood disturbances of chronic fatigue syndrome and seasonal affective disorder, or SAD, which are more common during winter.
Author of the report and editor of Pain Treatment Topics, Stewart B. Leavitt, MA, PhD, notes that for many people sunshine is not an ample source of vitamin D during most of the year and the few foods containing the vitamin do not provide enough of it. “In our review of 22 clinical research studies persons with various pain and fatigue syndromes almost always lacked vitamin D, especially during winter months. When sufficient vitamin D supplementation was provided, the aches, pains, weakness, and related problems in most sufferers either vanished or were at least helped to a significant degree.”
The report mentions the following important points:
>> Vitamin D is a complex nutrient that actually functions as a hormone to benefit numerous body tissues and organs, including bones, muscles, and nerves.
>> A surprising majority of persons in many parts of the world, including the United States, do not get enough vitamin D from sunshine or foods.
>> The currently recommended adequate intake of vitamin D – up to 400 IU per day in children and 600 IU per day in adults – is outdated and too low. According to the research, most children and adults need at least 1000 IU per day, and persons with bone or muscle aches and pains could benefit from 2000 IU or more per day of supplemental vitamin D3 (also called cholecalciferol), especially during winter months.
>> Vitamin D supplements are generally safe if taken as directed. They interact with very few drugs or other agents, and are usually not harmful unless very high daily doses – such as, 50,000 IU or more – are taken for an extended period of time.
>> Vitamin D supplements are easy to take, usually have no side effects, and typically cost as little as 7 to 10 cents per day.
Besides the comprehensive **Research Report (50-pages, 170 references) -- titled “Vitamin D – A Neglected ‘Analgesic’ for Chronic Musculoskeletal Pain” -- there is available a shorter **Practitioner Briefing (7-pages) that summarizes the report and provides guidance for healthcare providers. Additionally, a special **Patient Brochure (6-pages) explains what vitamin D is, how it works, and how it can help in relieving aches and pains.
**All 3 documents are available for free access at:_http://pain-topics.org/vitamind
In conclusion, Leavitt stresses that vitamin D should not be viewed as a cure for all pain conditions, and it is not necessarily a replacement for other pain-relief treatments. “While further research would be helpful,” he says, “extra vitamin D should be considered for all persons in late fall or early winter, and especially for those who have developed aches and pains, or fatigue and mood disorders.”
'LET THE SUNSHINE IN' TO PROTECT YOUR HEART THIS WINTER
Loyola Researchers Find Sunshine Deficit May Diminish Vitamin D Levels and Harm Cardiovascular Health
MAYWOOD - The temperature might not be the only thing plummeting this winter. Many people also will experience a decrease in their vitamin D levels, which can play a role in heart disease, according to a new review article in Circulation.
Vitamin D deficiency results in part from reduced exposure to sunlight, which is common during cold weather months when days are shorter and more time is spent indoors.
"Chronic vitamin D deficiency may be a culprit in heart disease, high blood pressure and metabolic syndrome," said Sue Penckofer, PhD, RN, study author and professor, Marcella Niehoff School of Nursing, Loyola University Chicago.
The review article cited a number of studies that linked vitamin D deficiency to heart disease. These studies found rates of severe disease or death may be 30 to 50 percent higher among sun-deprived individuals with heart disease.
Penckofer and colleagues concluded that diet alone is not sufficient to manage vitamin D levels. Treatment options to correct this level, such as vitamin D2 or D3, may decrease the risk of severe disease or death from cardiovascular disorders. The preferred range in the body is 30 - 60 ng/mL of 25(OH) vitamin D.
"Most physicians do not routinely test for vitamin D deficiency," said Penckofer. "However, most experts would agree that adults at risk for heart disease and others who experience fatigue joint pain or depression should have their vitamin D levels measured."
Study authors also included Glen W. Sizemore, MD, emeritus professor of Medicine, Division of Endocrinology and Metabolism, Loyola University Chicago Stritch School of Medicine, and Diane E. Wallis, MD, Midwest Heart Specialists, Downers Grove, Ill.
Study helps clarify role of vitamin D in cancer therapy
A colon cancer cell isn't a lost cause. Vitamin D can tame the rogue cell by adjusting everything from its gene expression to its cytoskeleton. In the Nov. 17 issue of the Journal of Cell Biology, Ordóñez-Morán et al. show that one pathway governs the vitamin's diverse effects. The results help clarify the actions of a molecule that is undergoing clinical trials as a cancer therapy.
Vitamin D stymies colon cancer cells in two ways. It switches on genes such as the one that encodes E-cadherin, a component of the adherens junctions that anchor cells in epithelial layers. The vitamin also induces effects on the cytoskeleton that are required for gene regulation and short-circuiting the Wnt/b-catenin pathway, which is overactive in most colon tumors. The net result is to curb division and prod colon cancer cells to differentiate into epithelial cells that settle down instead of spreading.
To delve into the mechanism, the team dosed colon cancer cells with calcitriol, the metabolically active version of vitamin D. Calcitriol triggered a surge of calcium into the cells and the subsequent switching on of RhoA–RhoGTPases, which have been implicated in the cytoskeletal changes induced by vitamin D. The activated RhoA in turn switched on one of its targets, the rho-associated coiled kinase (ROCK), which then roused two other kinases. Each step in this nongenomic pathway was necessary to spur the genomic responses, the researchers showed. The team also nailed down the contribution of the vitamin D receptor (VDR). The receptor was crucial at the beginning of the pathway, where it permitted the calcium influx, and at the end, where it activated and repressed genes.
The study is the first to show that vitamin D's genomic and nongenomic effects integrate to regulate cell physiology. One question the researchers now want to pursue is whether VDR from different locations—the nucleus, the cytosol, and possibly the cell membrane—has different functions in the pathway.
Low Vitamin D Levels Pose Large Threat to Health; Overall 26 Percent Increased Risk of Death
Researchers at Johns Hopkins are reporting what is believed to be the most conclusive evidence to date that inadequate levels of vitamin D, obtained from milk, fortified cereals and exposure to sunlight, lead to substantially increased risk of death.
In a study set to appear in the Archives of Internal Medicine online Aug. 11, the Johns Hopkins team analyzed a diverse sample of 13,000 initially healthy men and women participating in an ongoing national health survey and compared the risk of death between those with the lowest blood levels of vitamin D to those with higher amounts. An unhealthy deficiency, experts say, is considered blood levels of 17.8 nanograms per milliliter or lower.
Of the 1,800 study participants known to have died by Dec. 31, 2000, nearly 700 died from some form of heart disease, with 400 of these being deficient in vitamin D. This translates overall to an estimated 26 percent increased risk of any death, though the number of deaths from heart disease alone was not large enough to meet scientific criteria to resolve that it was due to low vitamin D levels.
Yet, researchers say it does highlight a trend, with other studies linking shortages of vitamin D to increased rates of breast cancer and depression in the elderly. And earlier published findings by the team, from the same national study, have established a possible tie-in, showing an 80 percent increased risk of peripheral artery disease from vitamin D deficits.
Researchers note that other studies in the last year or so in animals and humans have identified a connection between low levels of vitamin D and heart disease. But these studies, they say, were weakened by small sample numbers, lack of diversity in the population studied and other factors that limited scientists' ability to generalize the findings to the public at large.
"Our results make it much more clear that all men and women concerned about their overall health should more closely monitor their blood levels of vitamin D, and make sure they have enough," says study co-lead investigator Erin Michos, M.D., M.H.S.
"We think we have additional evidence to consider adding vitamin D deficiency as a distinct and separate risk factor for death from cardiovascular disease, putting it alongside much better known and understood risk factors, such as age, gender, family history, smoking, high blood cholesterol levels, high blood pressure, lack of exercise, obesity and diabetes," says Michos. Vitamin D is well known to play an essential role in cell growth, in boosting the body's immune system and in strengthening bones.
"Now that we know vitamin D deficiency is a risk factor, we can better assess how aggressively to treat people at risk of heart disease or those who are already ill and undergoing treatment," says Michos, who adds that test screening for nutrient levels is relatively simple. It can, she says, be made part of routine blood work and done while monitoring other known risk factors, including blood pressure, glucose and lipid levels.
Heart disease remains the nation's leading cause of death, killing more than a million Americans each year. Nearly 10 percent of those with the condition have not one identifiable, traditional risk factor, which the experts say is why a considerable extent of the disease goes unexplained.
Michos, an assistant professor at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute, recommends that people boost their vitamin D levels by eating diets rich in such fish as sardines and mackerel, consuming fortified dairy products, taking cod-liver oil and vitamin supplements, and in warmer weather briefly exposing skin to the sun's vitamin-D producing ultraviolet light.
Aware of the cancer risks linked to too much time spent in the sun, she says as little as 10 to 15 minutes of daily exposure to the sun can produce sufficient amounts of vitamin D to sustain health. The hormone-like nutrient controls blood levels of calcium and phosphorus, essential chemicals in the body.
If vitamin supplements are used, Michos says there is no evidence that more than 2,000 international units per day do any good. Study results show that heart disease death rates flattened out in participants with the highest vitamin D levels (above 50 nanograms per milliliter of blood), signaling a possible loss of the vitamin's protective effects at too-high doses.
The U.S. Institute of Medicine suggests that an adequate daily intake of vitamin D is between 200 and 400 international units (or blood levels nearing 30 nanograms per milliliter). Previous results from the same nationwide survey showed that 41 percent of men and 53 percent of women are technically deficient in the nutrient, with vitamin D levels below 28 nanograms per milliliter.
Michal Melamed, M.D., M.H.S., study co-lead investigator who started the research as a clinical fellow at Johns Hopkins, says no one knows yet why or how vitamin D's hormone-like properties may protect the heart, but she adds that there are plenty of leads in the better known links the vitamin has to problems with muscle overgrowth and high blood pressure, in addition to its control of inflammation, which scientists are showing plays a stronger role in all kinds of heart disease. But more research is needed to determine the nutrient's precise biological action.
Researchers say their next steps are to test various high doses of vitamin D to find out if the nutritional supplementation results in fewer deaths and lower incidence of heart disease, including heart attack or moments of prolonged and severe chest pain.
The team also plans to investigate what biological triggers, such as obesity or hypertension, might offset or worsen the action of vitamin D on heart muscle, or whether vitamin D sets off some other reaction in the heart.
Melamed says that because vitamin D levels are known to fluctuate in direct proportion with daily physical activity, the growing epidemic of obesity and indoor sedentary lifestyles lend more urgency to act on the vitamin D factor.
Vitamin D a key player in overall health of several body organs
Essential for life in higher animals, vitamin D, once linked to only bone diseases such as rickets and osteoporosis, is now recognized as a major player in contributing to overall human health, emphasizes UC Riverside's Anthony Norman, an international expert on vitamin D.
In a paper published in the August issue of the American Journal of Clinical Nutrition, Norman identifies vitamin D's potential for contributions to good health in the adaptive and innate immune systems, the secretion and regulation of insulin by the pancreas, the heart and blood pressure regulation, muscle strength and brain activity. In addition, access to adequate amounts of vitamin D is believed to be beneficial towards reducing the risk of cancer.
Norman also lists 36 organ tissues in the body whose cells respond biologically to vitamin D. The list includes bone marrow, breast, colon, intestine, kidney, lung, prostate, retina, skin, stomach and the uterus.
According to Norman, deficiency of vitamin D can impact all 36 organs. Already, vitamin D deficiency is associated with muscle strength decrease, high risk for falls, and increased risk for colorectal, prostate and breast and other major cancers.
"It is becoming increasingly clear to researchers in the field that vitamin D is strongly linked to several diseases," said Norman, a distinguished professor emeritus of biochemistry and of biomedical sciences who has worked on vitamin D for more than 45 years. "Its biological sphere of influence is much broader than we originally thought. The nutritional guidelines for vitamin D intake must be carefully reevaluated to determine the adequate intake, balancing sunlight exposure with dietary intake, to achieve good health by involving all 36 target organs."
Vitamin D is synthesized in the body in a series of steps. First, sunlight's ultraviolet rays act on a precursor compound in skin. When skin is exposed to sunlight, a sterol present in dermal tissue is converted to vitamin D, which, in turn, is metabolized in the liver and kidneys to form a hormone. It was Norman's laboratory that discovered, in 1967, that vitamin D is converted into a steroid hormone by the body.
The recommended daily intake of vitamin D is 200 international units (IU) for people up to 50 years old. The recommended daily intake of vitamin D is 400 IU for people 51 to 70 years old and 600 IU for people over 70 years old. Norman's recommendation for all adults is to have an average daily intake of at least 2000 IU.
"To optimize good health you must have enough vitamin D," he said. "Vitamin D deficiency is also especially of concern in third world countries that have poor nutritional practices and religious customs that require the body to be covered from head to toe. Ideally, to achieve the widest frequency of good health by population, we need to have 90 percent of the people with adequate amounts of vitamin D."
About half of the elderly in North America and two-thirds of the rest of the world are not getting enough vitamin D to maintain healthy bone density, lower their risks for fracture and improve tooth attachment.
"There needs to be a sea change by various governmental agencies in terms of the advice they present to citizens about how much vitamin D should be taken," Norman said. "The tendencies of people to live in cities where tall buildings block adequate sunlight from reaching the ground, to spend most of their time indoors, to use synthetic sunscreens that block ultraviolet rays, and to live in geographical regions of the world that do not receive adequate sunlight all contribute to the inability of the skin to biosynthesize sufficient amounts of vitamin D."
Found in minute amounts in food, vitamins are organic substances that higher forms of animals need to grow and sustain normal health. Vitamins, however, are not synthesized in sufficient amounts to meet bodily needs. Therefore, the body must acquire them through diet or in the form of supplements.
Because it is found in very few foods naturally, milk and other foods (often orange juice) are fortified with vitamin D.
While deficiency of vitamin D impacts health negatively, ingestion of extremely high doses of vitamin D can cause hypercalcemia, a condition in which the blood's calcium level is above normal. The highest daily 'safe' dose of vitamin D is 10,000 IU.
"More than ever we need to increase the amount of research on vitamin D, with more funding from government agencies and pharmaceutical companies, to meet the challenge of preserving or improving the health of everyone on the planet," Norman said.
Lack of vitamin D linked to Parkinson's disease
A majority of Parkinson's disease patients had insufficient levels of vitamin D in a new study from Emory University School of Medicine.
The fraction of Parkinson's patients with vitamin D insufficiency, 55 percent, was significantly more than patients with Alzheimer's disease (41 percent) or healthy elderly people (36 percent).
The results are published in the October issue of Archives of Neurology.
The finding adds to evidence that low vitamin D is associated with Parkinson's, says first author Marian Evatt, MD, assistant professor of neurology at Emory.
Evatt is assistant director of the Movement Disorders Program at Wesley Woods Hospital. The senior author is endocrinologist Vin Tangpricha, MD, assistant professor of medicine at Emory and director of the Endocrine Clinical Research Unit.
Evatt says her team compared Parkinson's patients to Alzheimer's patients because they wanted to evaluate the possibility that neurodegenerative diseases in general lead to vitamin D insufficiency.
Most Americans get the majority of their vitamin D from exposure to sunlight or by dietary supplements; fortified foods such as milk and packaged cereals are a minor source. Only a few foods in nature contain substantial amounts of vitamin D, such as salmon and tuna.
The body's ability to produce vitamin D using UV-B radiation from the sun decreases with age, making older individuals at increased risk of vitamin D deficiency.
"We found that vitamin D insufficiency may have a unique association with Parkinson's, which is intriguing and warrants further investigation," Evatt says.
The connection could come partly because patients with Parkinson's have mobility problems and are seldom exposed to the sun, or because low vitamin D levels are in some way related to the genesis or progression of the disease.
She says her team saw their results as striking because their study group came from the Southeast, not a region with long gloomy winters, where vitamin D insufficiency is thought to be more of a problem.
In addition, the study found that the fraction of patients with the lowest levels of vitamin D, described as vitamin D deficiency, was higher (23 percent) in the Parkinson's group than the Alzheimer's group (16 percent) or the healthy group (10 percent).
The retrospective study examined 100 people in each group, who were recruited between 1992 and 2007. Every fifth Parkinson's patient from Emory's clinical neurology database was selected, then healthy controls and patients with Alzheimer's disease were matched on age and state of residence.
Vitamin D insufficiency is frequently defined as less than 30 nanograms per milliliter of blood of the 25-hydroxy form (the major storage form) of the vitamin and deficiency as less than 20 nanograms per milliliter. However, most experts agree insufficiency warrants treatment and should not be ignored.
Doctors have known for decades that vitamin D plays a role in bone formation, Evatt says. More recently, scientists have been uncovering its effects elsewhere, including producing peptides that fight microbes in the skin, regulating blood pressure and insulin levels, and maintaining the nervous system. Low vitamin D levels also appear to increase the risk of several cancers and auto-immune diseases such as multiple sclerosis and diabetes.
Parkinson's disease affects nerve cells in several parts of the brain, particularly those that use the chemical messenger dopamine to control movement. The most common symptoms are tremor, stiffness and slowness of movement. These can be treated with oral replacement of dopamine.
Previous studies have shown that the part of the brain affected most by Parkinson's, the substantia nigra, has high levels of the vitamin D receptor, which suggests vitamin D may be important for normal functions of these cells, Evatt says.
Emory clinicians are conducting further research to investigate whether vitamin D insufficiency is a cause or possibly a result of having Parkinson's. In a pilot study, Parkinson's patients are receiving either standard or larger doses of vitamin D, with an eye towards possibly reducing the severity of their condition.
Current Vitamin D Recommendations Merely a Fraction of Safe and Perhaps Essential Levels for Children
The current recommended daily allowance (RDA) of vitamin D for children is 200 International Units (IUs), but new research reveals that children may need and can safely take ten-times that amount. According to a recently accepted report in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM), this order-of-magnitude increase could improve the bone health of children worldwide and may have other long-term health benefits.
“Our research reveals that vitamin D, at doses equivalent to 2,000 IUs a day, is not only safe for adolescents, but it is actually necessary for achieving desirable vitamin D levels,” said Ghada El-Haff Fuleihan, M.D., of the American University of Beirut-Medical Center, Lebanon, and lead author of the study.
Vitamin D is an essential hormone for bone growth and development in children and promotes skeletal health in adults. Currently, the National Academy of Sciences’ Institute of Medicine recommends an adequate daily intake of 200 IUs of vitamin D for children. This is also the recommendation from the American Academy of Pediatrics. These levels, however, may not be adequate for bone growth and musculoskeletal health in children and adolescents.
“Data on appropriate vitamin D levels in the pediatric age group are lacking,” said Dr. Fuleihan. “This is a major obstacle to finding the right daily allowance to enhance musculoskeletal health.”
To help clarify these important guidelines, Fuleihan and his colleagues conducted both short- and long-term trials to gauge the safety of relatively high doses of vitamin D3 in children ages 10-17 years.
Vitamin D3 is one of the most common forms of vitamin D, and is easily converted to 25-OHD (25-hydroxyvitamin), which is the active form of vitamin D found in the blood.
For this placebo-controlled study, researchers gave children various doses of vitamin D at various intervals and measured the impact this had on serum levels of 25-OHD.
For the short-term study, 25 students (15 boys and 10 girls) received one-weekly, 14,000 IU doses of vitamin D for eight weeks. Serum levels of 25-OHD were then measured for an additional eight weeks. This portion of the test was conducted during the summer and early fall, when the highest natural levels of vitamin D are reached.
For the long-term, one-year study, 340 students (172 boys and 168 girls) received either a low dose of vitamin D (1,400 IUs each week) or a high dose (14,000 IUs each week).
Only children given the equivalent of 2,000 IUs a day of vitamin D increased 25-OHD levels from the mid-teens to the mid-thirties (ng/ml)—the level considered optimal for adults. None of the children in either trial showed any evidence for vitamin D intoxication.
Although many experts agree that a 25-OHD level of 30 ng/ml is desirable in adults, what constitutes an optimal D level for children and adolescents is more debatable. According to the researchers, due to rapid skeletal growth, children and adolescents are more likely to be vitamin D deficient, and are far less likely to reach vitamin D levels that doctors would consider toxic.
“Supplementation of children and adolescents with 2,000 IUs a day of vitamin D3 is well tolerated and safe,” said Dr. Fuleihan. “This is particularly relevant in light of the increasingly recognized health benefits of vitamin D for adults and children.”
Other researchers involved in the study include Joyce Maalouf, Mona Nabulsi, Reinhold Vieth, Samantha Kimball, Rola El-Rassi, and Ziyad Mahfoud.
The study “Short term and long term safety of weekly high dose vitamin D3 supplemetnation in school children” will be published in the July issue of JCEM.
Oral vitamin D may help prevent some skin infections
A study led by researchers at the University of California, San Diego School of Medicine suggests that use of oral Vitamin D supplements bolsters production of a protective chemical normally found in the skin, and may help prevent skin infections that are a common result of atopic dermatitis, the most common form of eczema.
The study – led by Richard Gallo, M.D., Ph.D., professor of medicine and chief of the Division of Dermatology at the UCSD School of Medicine and the Dermatology section of the Veterans Affairs San Diego Healthcare System, and Tissa R. Hata, M.D., associate professor of medicine at UC San Diego – found that use of oral vitamin D appeared to correct a defect in the immune systems in patients with this skin disease. Their findings will be published in the October 3 edition of the Journal of Allergy & Clinical Immunology
The researchers studied a small number of patients with moderate to severe atopic dermatitis, a chronic skin disease that affects 10 to 20 percent of children and one to three percent of adults. Atopic dermatitis is characterized by areas of severe itching, redness and scaling. Over time, chronic changes can occur due to constant scratching and rubbing. The condition puts patients at increased risk for skin infections by Staph aureus and the herpes and small pox viruses.
It had previously been shown that defects in the immune system interfere with the skin's ability to produce a peptide called cathelicidin, which is protective against microbial invasion. In many skin diseases, including eczema, a deficiency of cathelicidin correlates with increased infection.
Study participants (14 with atopic dermatitis and 14 without) were all given 4000 IUs of oral Vitamin D3 (cholecalciferol) per day for 21 days. Skin lesions were biopsied before and after the 21-day period. The researchers found that oral vitamin D use by the patients appeared to correct the skin's defect in cathelicidin.
"These results suggest that supplementation with oral vitamin D dramatically induces cathelicidin production in the skin of patients with atopic dermatitis," said Hata. "It also slightly elevated its production in normal skin in this study."
However, the researchers caution that this was a small study and that further research is needed to evaluate the long-term effects of vitamin D supplementation, and to determine if this may be an adequate way to prevent infections in patients with atopic dermatitis.
In the past several years, vitamin D deficiency has been linked to increased rates of multiple cancers and diabetes, among other diseases, notably in studies published by UC San Diego researcher, Cedric Garland, Dr. P.H., professor with Moores UCSD Cancer Center and the Department of Family and Preventive Medicine at UC San Diego.
Vitamin D findings point to new treatment for heart failure
Strong bones, a healthy immune system, protection against some types of cancer: Recent studies suggest there’s yet another item for the expanding list of Vitamin D benefits. Vitamin D, “the sunshine vitamin,” keeps the heart, the body’s long-distance runner, fit for life’s demands.
University of Michigan pharmacologist Robert U. Simpson, Ph.D., thinks it’s apt to call vitamin D “the heart tranquilizer.”
In studies in rats, Simpson and his team report the first concrete evidence that treatment with activated vitamin D can protect against heart failure. Their results appear in the July issue of the Journal of Cardiovascular Pharmacology.
In the study, treatments with activated vitamin D prevented heart muscle cells from growing bigger – the condition, called hypertrophy, in which the heart becomes enlarged and overworked in people with heart failure. The treatments prevented heart muscle cells from the over-stimulation and increased contractions associated with the progression of heart failure.
Simpson and his colleagues have explored vitamin D’s effects on heart muscle and the cardiovascular system for more than 20 years. In 1987, when Simpson showed the link between vitamin D and heart health, the idea seemed far-fetched and research funding was scarce. Now, a number of studies worldwide attest to the vitamin D-heart health link (see citations below).
The new heart insights add to the growing awareness that widespread vitamin D deficiency—thought to affect one-third to one-half of U.S. adults middle-aged and older—may be putting people at greater risk of many common diseases. Pharmaceutical companies are developing anti-cancer drugs using vitamin D analogs, which are synthetic compounds that produce vitamin D’s effects. There’s also increasing interest in using vitamin D or its analogs to treat autoimmune disorders.
In more than a dozen types of tissues and cells in the body, activated vitamin D acts as a powerful hormone, regulating expression of essential genes and rapidly activating already expressed enzymes and proteins. In the heart, Simpson’s team has revealed precisely how activated vitamin D connects with specific vitamin D receptors and produces its calming, protective effects. Those results appeared in the February issue of Endocrinology.
Sunlight causes the skin to make activated vitamin D. People also get vitamin D from certain foods and vitamin D supplements. Taking vitamin D supplements and for many people, getting sun exposure in safe ways, are certainly good options for people who want to keep their hearts healthy. But people with heart failure or at risk of heart failure will likely need a drug made of a compound or analog of vitamin D that will more powerfully produce vitamin D’s effects in the heart if they are to see improvement in their symptoms, Simpson says.
Vitamin D analogs already are on the market for some conditions. One present drawback of these compounds is that they tend to increase blood calcium to undesirable levels. Simpson’s lab is conducting studies of a specific analog which may be less toxic, so efforts to develop a vitamin D-based drug to treat heart failure are moving a step closer to initial trials in people.
Men with vitamin D deficiency may have increased risk of heart attack
Low levels of vitamin D appear to be associated with higher risk of myocardial infarction (heart attack) in men, according to a report in the June 9 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Studies have shown that the rates of cardiovascular disease-related deaths are increased at higher latitudes and during the winter months and are lower at high altitudes, according to background information in the article. "This pattern is consistent with an adverse effect of hypovitaminosis D [vitamin D deficiency], which is more prevalent at higher latitudes, during the winter and at lower altitudes," the authors write. While other explanations are possible, vitamin D has been shown to affect the body in ways that may influence the risk of heart attack or heart disease.
Edward Giovannucci, M.D., Sc.D., of Harvard School of Public Health and Brigham and Women's Hospital, Boston, and colleagues reviewed medical records and blood samples of 454 men (age 40 to 75) who had non-fatal heart attack or fatal heart disease from the date of blood collection (between January 1993 and December 1995) until January 2004. They then compared the data from these men with records and blood samples of 900 living men who did not have a history of cardiovascular disease. The men's diet and lifestyle factors, recorded by self-administered questionnaires were also noted.
Men with a vitamin D deficiency (having 15 nanograms per milliliter of blood or less) had an increased risk for heart attack compared with those with a sufficient amount (having 30 nanograms per milliliter of blood or more) of vitamin D. "After additional adjustment for family history of myocardial infarction, body mass index, alcohol consumption, physical activity, history of diabetes mellitus and hypertension, ethnicity, region, marine omega 3 intake, low- and high-density lipoprotein cholesterol levels and triglyceride levels, this relationship remained significant," the authors write. Men with intermediate levels of vitamin D had a higher risk of heart attack than those with sufficient vitamin D levels.
"Vitamin D deficiency has been related to an increasing number of conditions and to total mortality. These results further support an important role for vitamin D in myocardial infarction risk," the authors conclude. "Thus, the present findings add further support that the current dietary requirements of vitamin D need to be increased to have an effect on circulating 25(OH)D [vitamin D] levels substantially large enough for potential health benefits."
2 new studies back vitamin D for cancer prevention
Two new vitamin D studies using a sophisticated form of analysis called meta-analysis, in which data from multiple reports is combined, have revealed new prescriptions for possibly preventing up to half of the cases of breast cancer and two-thirds of the cases of colorectal cancer in the United States. The work was conducted by a core team of cancer prevention specialists at the Moores Cancer Center at University of California, San Diego (UCSD), and colleagues from both coasts.
The breast cancer study, published online in the current issue of the Journal of Steroid Biochemistry and Molecular Biology, pooled dose-response data from two earlier studies - the Harvard Nurses Health Study and the St. George's Hospital Study - and found that individuals with the highest blood levels of 25-hydroxyvitamin D, or 25(OH)D, had the lowest risk of breast cancer._
The researchers divided the 1,760 records of individuals in the two studies into five equal groups, from the lowest blood levels of 25(OH)D (less than 13 nanograms per milliliter, or 13 ng/ml) to the highest (approximately 52 ng/ml). The data also included whether or not the individual had developed cancer.
"The data were very clear, showing that individuals in the group with the lowest blood levels had the highest rates of breast cancer, and the breast cancer rates dropped as the blood levels of 25-hydroxyvitamin D increased," said study co-author Cedric Garland, Dr.P.H. "The serum level associated with a 50 percent reduction in risk could be maintained by taking 2,000 international units of vitamin D3 daily plus, when the weather permits, spending 10 to 15 minutes a day in the sun."
The colorectal cancer study, published online February 6 in the American Journal of Preventive Medicine, is a meta-analysis of five studies that explored the association of blood levels of 25(OH)D with risk of colon cancer. All of the studies involved blood collected and tested for 25 (OH)D levels from healthy volunteer donors who were then followed for up to 25 years for development of colorectal cancer._
As with the breast cancer study, the dose-response data on a total of 1,448 individuals were put into order by serum 25(OH)D level and then divided into five equal groups, from the lowest blood levels to the highest.
"Through this meta-analysis we found that raising the serum level of 25-hydroxyvitamin D to 34 ng/ml would reduce the incidence rates of colorectal cancer by half," said co-author Edward D. Gorham, Ph.D. "We project a two-thirds reduction in incidence with serum levels of 46ng/ml, which corresponds to a daily intake of 2,000 IU of vitamin D3. This would be best achieved with a combination of diet, supplements and 10 to 15 minutes per day in the sun."_
Vitamin D3 is available through diet, supplements and exposure of the skin to sunlight, or ultraviolet B (UVB). In the paper, the researchers underscored the importance of limiting sun exposure such that the skin does not change color (tan) or burn. For a typical fair-skinned Caucasian individual, adequate vitamin D could be photosynthesized safely by spending 10 to 15 minutes in the noontime sun on a clear day with 50 percent of skin area exposed to the sun. Darker skinned individuals may require more time in the sun, such as 25 minutes. For people with photosensitivity disorders, or anyone with a personal or family history of nonmelanoma skin cancer, any amount of extra sun exposure would be inadvisable.
A larger daily dose of vitamin D could reduce the incidence of colorectal cancer with minimal risk, according to a new review that pools results from five studies._
The analysis found that maintaining a specific target blood level of vitamin D was associated with a 50 percent lower risk of colorectal cancer than that seen in people with consistently lower blood levels._
Previous studies had shown that lower blood levels of vitamin D did not protect against colorectal cancer, according to lead author Edward Gorham, Ph.D., a research epidemiologist with the Naval Health Research Center in San Diego. However, a meta-analysis pools the data from several studies, thus increasing the strength of the results._
The study is being published in the March issue of the American Journal of Preventive Medicine._
The five studies looked at serum collected from healthy volunteers who were then followed for periods ranging from two years to 25 years. There were 535 cases in the pooled analysis and 913 controls, or 1,448 total participants._
The researchers found that a blood serum vitamin D level of 33 nanograms per milliliter or higher was associated with a 50 percent lower risk of colorectal cancer than that seen with blood levels of 12 nanograms per milliliter or lower.
Vitamin D levels in the body are a factor of both diet and sun exposure. Exposing the skin to the sun lets the body synthesize vitamin D, which is why mortality due to colorectal cancer may be higher in geographic areas that get less sunshine._
The amount of dietary vitamin D needed to reach the serum levels that appear to be protective against colorectal cancer — 1,000 to 2,000 international units a day — would not pose any risk, according to Gorham: “The Institute of Medicine has set a ‘No Adverse Effect Level’ of 2,000 IU per day for vitamin D intake, so this recommendation would be safe for most people.”
There is no official recommended dietary allowance for vitamin D, but an adequate dietary intake per day for most adults is currently considered to be 200 to 400 IU._
Small amounts of sun exposure would also help people boost their vitamin D levels. Fifteen to 20 minutes per day without sunscreen is enough for the body to synthesize 10,000 IU of vitamin D with minimal risk of sunburn or skin cancer, Gorham said.
“The results are pretty straightforward,” said Karen Glanz, Ph.D., director of Emory University’s Prevention Research Center at the Rollins School of Public Health. However, changing behavior on the basis of this study may be premature, she said. The analysis found an association between vitamin D levels and lowered risk, not a definite link, Glanz said, but adding vitamin D to the diet or taking a supplement would probably not do much harm and there could be a benefit.__The meta-analysis on colorectal cancer includes data from the Women's Health Initiative, which had shown in 2006 that a low dose of vitamin D did not protect against colorectal cancer within seven years of follow-up. However, the researchers wrote, the meta-analysis indicates that a higher dose may reduce its incidence.__"Meta-analysis is an important tool for revealing trends that may not be apparent in a single study," said co-author Sharif B. Mohr, M.P.H. "Pooling of independent but similar studies increases precision, and therefore the confidence level of the findings."
Winter Sun Makes It Difficult to Get Vitamin D Naturally
As the days grow shorter, the sun’s warm rays aren’t the only thing your body may be missing, warns Creighton University researcher Joan Lappe, Ph.D.
If you live in North American at latitudes above the 37th parallel – Omaha is near the 41st parallel - you also may not be getting enough vitamin D, says Lappe, professor of medicine and holder of the Criss/Beirne Endowed Chair in the Creighton School of Nursing.
And that vitamin D is important to your health. In fact, a landmark study by Lappe and other Creighton researchers, published in June in the American Journal of Clinical Nutrition, showed a direct link between vitamin D and cancer prevention._Humans can get vitamin D from several sources.
During the summer, the body can convert solar energy into ample amounts of vitamin D with just 10-15 minutes exposure daily to the sun. That’s not possible this time of year.
“From October until the end of March, the angle of the sun is such that, in much of North America, no vitamin D is available from that source,” Lappe says. “What that means is most of us are deficient in vitamin D this time of year.”
While you can get the vitamin from fish oil and a few fortified foods, it’s difficult to take in adequate amounts of vitamin D by eating alone. Lappe recommends taking vitamin D3 – the same form of the vitamin that humans make from exposure to the sun.
The amount of vitamin D you should take daily is a subject of great debate, Lappe notes.
The U.S. government’s recommended daily allowance is 200 IU until age 50, 400 IU for 50-70 year olds, and 600 IU after age 70. However, many medical experts believe those recommendations are way too low.
The Canadian Cancer Society recently recommended that people with light skin take 1,000 IU of the vitamin supplement during fall and winter, while people with darker skin or limited sun exposure take that amount throughout the year.
The society’s recommendation coincided with the publication of the Creighton (Cray-ton) research in June. The four-year study involving 1,179 Nebraska women showed that women taking calcium supplements plus 1,100 IU of vitamin D3 daily, experienced a 60 percent decrease in their risk of developing cancer than a placebo group.
“Generally, medical experts consider it safe to take between 1,000 IU and 2,000 IU of vitamin D supplements daily,” Lappe says.
Vitamin D Reduces Cancer Risk - Sun Not Enough
Most Americans and others are not taking enough vitamin D, a fact that may put them at significant risk for developing cancer, according to a landmark study conducted by Creighton University School of Medicine.
The four-year, randomized study followed 1,179 healthy, postmenopausal women from rural eastern Nebraska.* Participants taking calcium, as well as a quantity of vitamin D3 nearly three times the U.S. government’s Recommended Daily Amount (RDA) for middle-age adults, showed a dramatic 60 percent or greater reduction in cancer risk than women who did not get the vitamin.
The results of the study, conducted between 2000 and 2005, were reported in the June 8 online edition of the American Journal of Clinical Nutrition.
“The findings are very exciting. They confirm what a number of vitamin D proponents have suspected for some time but that, until now, have not been substantiated through clinical trial,” said principal investigator Joan Lappe, Ph.D., R.N., Creighton professor of medicine and holder of the Criss/Beirne Endowed Chair in the School of Nursing. “Vitamin D is a critical tool in fighting cancer as well as many other diseases.”
Research participants were all 55 years and older and free of known cancers for at least 10 years prior to entering the Creighton study. Subjects were randomly assigned to take daily dosages of 1,400-1,500 mg supplemental calcium, 1,400-1,500 mg supplemental calcium plus 1,100 IU of vitamin D3, or placebos. National Institutes of Health funded the study.
Over the course of four years, women in the calcium/vitamin D3 group experienced a 60 percent decrease in their cancer risk than the group taking placebos.
On the premise that some women entered the study with undiagnosed cancers, researchers then eliminated the first-year results and looked at the last three years of the study. When they did that, the results became even more dramatic with the calcium/vitamin D3 group showing a startling 77 percent cancer-risk reduction.
In the three-year analysis, there was no statistically significant difference in cancer incidence between participants taking placebos and those taking just calcium supplements.
Through the course of the study, 50 participants developed nonskin cancers, including breast, colon, lung and other cancers.
Lappe said further studies are needed to determine whether the Creighton research results apply to other populations, including men, women of all ages, and different ethnic groups. While the study was open to all ethnic groups, all participants were Caucasian, she noted.
There is a growing body of evidence that a higher intake of vitamin D may be helpful in the prevention and treatment of cancer, high blood pressure, fibromyalgia, diabetes mellitus, multiple sclerosis, and rheumatoid arthritis and other diseases.
Humans make their own vitamin D3 when they are exposed to sunlight. In fact, only 10-15 minutes a day in a bright summer sun creates large amounts of the vitamin, Lappe said. However, people need to exercise caution since the sun’s ultraviolet B rays also can cause skin cancer; sunscreen blocks most vitamin D production.
In addition, the latitude at which you live and your ancestry also influence your body’s ability to convert sunlight into vitamin D. People with dark skin have more difficulty making the vitamin. Persons living at latitudes north of the 37th parallel – Omaha is near the 41st parallel – cannot get their vitamin D naturally during the winter months because of the sun’s angle.
Experts generally agree that the RDA** for vitamin D needs to be increased substantially, however there is debate about the amount. Supplements are available in two forms – vitamin D2 and vitamin D3. Creighton researchers recommend vitamin D3 , because it is more active and thus more effective in humans.
It’s not yet clear why overweight elderly adults have low levels of vitamin D in their blood. However, researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (USDA HNRCA) have found that lack of sun exposure may not account for low levels of vitamin D in elders who are overweight.
“People aged 65 and over with high percent body fat have lower levels of 25-hydroxyvitamin D, the storage form of vitamin D, compared to those who have lower percent body fat,” says corresponding author Susan Harris, DSc, epidemiologist in the Bone Metabolism Laboratory at the USDA HNRCA.
Harris and co-author Bess Dawson-Hughes, MD, director of the Bone Metabolism Laboratory at the USDA HNRCA, interviewed 381 Caucasian men and women aged 65 and over about their sun exposure over a previous three-month period.
Individuals reported how much time they spent outdoors, how much skin was exposed while outdoors, and whether or not they wore sunscreen. Seasonality, or when the individual entered the study, was also taken into account, because in Boston, where the study was conducted, sun rays are weak in winter compared with summer months. The researchers measured participants’ percent body fat using dual-energy x-ray absorptiometry (DXA), a precise method for determining body composition. Individuals were grouped into quartiles of percent body fat: less than 28 percent, 28 percent to 33 percent, 34 percent to 40 percent, and greater than 40 percent. Blood levels of 25-hydroxyvitamin D were measured and participants were asked to fill out a dietary questionnaire to measure the amount of vitamin D they obtained from food.
Harris and Dawson-Hughes found that when adjusted for sex, age, seasonality and dietary vitamin D intake, 25-hydroxyvitamin D significantly decreased as body fat increased, (P<0.024). When the researchers further adjusted for sunlight exposure variables, 25-hydroxyvitamin D values still significantly decreased as body fat increased. “Sunlight exposure could not account for low vitamin D stores in older people with high percent body fat,” explains Harris.
Vitamin D is called the “sunshine vitamin” because it is produced by the body when the skin is exposed to ultraviolet (UV) rays from the sun. Vitamin D can also be obtained from foods such as fish and fortified milk and from supplements. When this fat-soluble vitamin enters the body it is converted in the liver to 25-hydroxyvitamin D. This is one of several important forms of vitamin D, and is the form that researchers and clinicians use as an indicator of vitamin D status in individuals. “Vitamin D is especially critical in maintaining bone health, and there is evidence that many older Americans have low blood levels of vitamin D, which can put them at risk for bone fractures and osteoporosis,” says Dawson-Hughes, who is also a professor at Tufts University School of Medicine.
“These results cannot be carried over to other populations, such as young people, or elderly living in different climates. However, if low vitamin D stores are not attributed to low sunlight exposure in this population, it suggests that we should explore other possibilities,” says Harris. “The most likely explanation seems to be that vitamin D is sequestered in fat tissue, reducing its entry into the blood.”
Study shines more light on benefit of vitamin D in fighting cancer
600,000 cases a year of breast and colorectal cancer could be prevented each year by adequate intake of vitamin D, according to researcher
A new study looking at the relationship between vitamin D serum levels and the risk of colon and breast cancer across the globe has estimated the number of cases of cancer that could be prevented each year if vitamin D3 levels met the target proposed by researchers.
Cedric F. Garland, Dr.P.H., cancer prevention specialist at the Moores Cancer Center at the University of California, San Diego (UCSD) and colleagues estimate that 250,000 cases of colorectal cancer and 350,000 cases of breast cancer could be prevented worldwide by increasing intake of vitamin D3, particularly in countries north of the equator. Vitamin D3 is available through diet, supplements and exposure of the skin to sunlight.
“For the first time, we are saying that 600,000 cases of breast and colorectal cancer could be prevented each year worldwide, including nearly 150,000 in the United States alone,” said study co-author Garland. The paper, which looks at the dose-response relationship between vitamin D and cancer, will be published in the August edition of the journal Nutrition Reviews.
The study combined data from surveys of serum vitamin D levels during winter from 15 countries. It is the first such study to look at satellite measurements of sunshine and cloud cover in countries where actual blood serum levels of vitamin D3 had also been determined. The data were then applied to 177 countries to estimate the average serum level of a vitamin D metabolite of people living there.
The data revealed an inverse association of serum vitamin D with risk of colorectal and breast cancer. The protective effect began at levels ranging from 24 to 32 nanograms per milliliter of 25-hydroxyvitamin D concentration in the serum. The 25-hydroxyvitamin D level is the main indicator of vitamin D status. The late winter average 25-hydroxyvitamin D in the US is about 15-18 ng/ml. The researchers maintain that increasing vitamin D levels in populations, particularly those in northern climates, has the potential to both prevent and possibly serve as an adjunct to existing treatments for cancer.
The work builds on previous studies by Garland and colleagues (Journal of Steroid Biochemistry and Molecular, February 2007) which found that raising the serum 25(OH)D levels to 55 ng/mL was optimal for cancer prevention. This is the first study to recommend optimal vitamin D serum levels which, Garland said, are high enough to provide the needed benefit but which have been found by other scientists to be low enough to avoid health risks.
“This could be best achieved with a combination of diet, supplements and short intervals – 10 or 15 minutes a day – in the sun,” said Garland. It could be less for very fair-skinned individuals. He went on to say that “the appropriate dose of vitamin D in order to reach this level, could be very little in a lifeguard in Southern California… or quite a lot for someone in Northern Europe who tends to remain indoors most of the year.”
The serum level recommended by the study would correspond to intake of 2000 International Units per day of vitamin D3 for a meaningful reduction in colorectal cancer. The researchers recommend 2000 IU/day, plus, when weather allows, a few minutes in the sun with at least 40% of the skin exposed, for a meaningful reduction in breast cancer incidence, unless the individual has a history of skin cancer or a photosensitivity disease.
Garland also recommends moderate sun exposure and use of clothing and a hat when in the sun longer than 15 minutes.
This paper used worldwide data only recently available through a new tool called GLOBOCAN, developed by the World Health Organization’s International Agency for Research on Cancer. GLOBOCAN is a database of cancer incidence, mortality and prevalence for 177 countries. Previous studies from this core group have shown an association between higher levels of vitamin D3 or markers of vitamin D status and lower risk of cancers of the breast, colon, ovary and kidney. The researchers underscore their call for prompt public health action to increase intake of vitamin D3 as an inexpensive tool for prevention of diseases that claim nearly one million lives each year world wide.
“The message is, depending on where you live, you may need to consider taking in considerably higher levels of vitamin D3 than those currently recommended,” said Garland. “I’d recommend discussing vitamin D needs with a health care professional, who may order and interpret a simple blood test for a vitamin D metabolite [25(OH)D], and provide a dosage recommendation that’s appropriate for the individual’s needs.”
Vitamin D and breast cancer risk
A connection between vitamin D level and the risk of developing breast cancer has been implicated for a long time, but its clinical relevance had not yet been proven. Sascha Abbas and colleagues from the working group headed by Dr. Jenny Chang-Claude at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), collaborating with researchers of the University Hospitals in Hamburg-Eppendorf, have now obtained clear results: While previous studies had concentrated chiefly on nutritional vitamin D, the researchers have now investigated the complete vitamin D status. To this end, they studied 25-hydroxyvitamin D (25(OH)D) as a marker for both endogenous vitamin D and vitamin D from food intake.
The result of the study involving 1,394 breast cancer patients and an equal number of healthy women after menopause was surprisingly clear: Women with a very low blood level of 25(OH)D have a considerably increased breast cancer risk. The effect was found to be strongest in women who were not taking hormones for relief of menopausal symptoms. However, the authors note that, in this retrospective study, diagnosis-related factors such as chemotherapy or lack of sunlight after prolonged hospital stays might have contributed to low vitamin levels of breast cancer patients.
In addition, the investigators focused on the vitamin D receptor. The gene of this receptor is found in several variants known as polymorphisms. The research team of the DKFZ and Eppendorf Hospitals investigated the effect of four of these polymorphisms on the risk of developing breast cancer. They found out that carriers of the Taql polymorphism have a slightly increased risk of breast tumors that carry receptors for the female sex hormone estrogen on their surface. No effects on the overall breast cancer risk were found. A possible explanation offered by the authors is that vitamin D can exert its cancer-preventing effect by counteracting the growth-promoting effect of estrogens.
Besides its cancer-preventing influence with effects on cell growth, cell differentiation and programmed cell death (apoptosis), vitamin D regulates, above all, the calcium metabolism in our body. Foods that are particularly rich in vitamin D include seafish (cod liver oil), eggs and dairy products. However, the largest portion of vitamin D is produced by our own body with the aid of sunlight.
itamin D in brain function
Vitamin D supplementation for high risk groups may be warranted
In a definitive critical review, scientists at Children’s Hospital & Research Center Oakland ask whether there is convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction. Joyce C. McCann, Ph.D., assistant staff scientist and Bruce N. Ames, Ph.D., senior scientist at Children’s Hospital Oakland Research Institute (CHORI) conclude that there is ample biological evidence to suggest an important role for vitamin D in brain development and function, and that supplementation for groups chronically low in vitamin D is warranted. Their conclusions will be published on April 22, 2008 in the Federation of American Societies for Experimental Biology (FASEB) Journal.
“This critical analysis of vitamin D function and the brain is a model of careful thinking about nutrition and behavior”, says Gerald Weissmann, MD, Editor-in-Chief of the FASEB Journal “One wishes that all studies of nutritional supplements or requirements were this thoughtful. Drs. McCann and Ames deftly show that while vitamin D has an important role in the development and function of the brain, its exact effects on behavior remain unclear. Pointing to the need for further study, the authors argue for vitamin D supplementation in groups at risk.”
Vitamin D has long been known to promote healthy bones by regulating calcium levels in the body. Lack of sufficient vitamin D in very young children results in rickets, which can be easily prevented by vitamin D supplements. Only recently the scientific community has become aware of a much broader role for vitamin D. For example, we now know that, in addition to its role in maintaining bone health, vitamin D is involved in differentiation of tissues during development and in proper functioning of the immune system. In fact, over 900 different genes are now known to be able to bind the vitamin D receptor, through which vitamin D mediates its effects. In addition to protecting against rickets, evidence now strongly indicates that a plentiful supply of vitamin D helps to protect against bone fractures in the elderly. Evidence also continues to accumulate suggesting a beneficial role for vitamin D in protecting against autoimmune diseases, including multiple sclerosis and type I diabetes, as well as some forms of cancer, particularly colorectal and breast.
Vitamin D is present in only a few foods (e.g., fatty fish), and is also added to fortified milk, but our supply typically comes mostly from exposure to ultraviolet rays (UV) in sunlight. UV from the sun converts a biochemical in the skin to vitamin D, which is then metabolized to calcitriol, its active form and an important hormone. Formation of vitamin D by UV can be 6 times more efficient in light skin than dark skin, which is an important cause of the known widespread vitamin D deficiency among African Americans living in northern latitudes. Dark skin has been selected during evolution because it protects against the burning UV rays of the sun in the tropics. White skin has been selected for allowing as much UV exposure to make sufficient vitamin D in Northern (high) latitudes. Thus, fair-skinned northerners are at risk in Australia or Arizona for sunburns and UV-induced cancer, while dark-skinned people in the Northern U.S. or European latitudes with little exposure to the sun are at risk for rickets, bone fractures and possibly other diseases including several types of cancer due to a lack of vitamin D. Fortunately sun-screens and vitamin D supplements are inexpensive.
McCann & Ames point out that evidence for vitamin D’s involvement in brain function includes the wide distribution of vitamin D receptors throughout the brain. They also discuss vitamin D’s ability to affect proteins in the brain known to be directly involved in learning and memory, motor control, and possibly even maternal and social behavior. The review also discusses studies in both humans and animals that present suggestive though not definitive evidence of cognitive or behavioral consequences of vitamin D inadequacy. The authors discuss possible reasons for the apparent discrepancy between the biological and behavioral evidence, and suggest new, possibly clarifying avenues of research.
Many vitamin D experts advise that the currently recommended level of vitamin D intake is much too low and should be raised to protect against bone fractures and possibly cancer in addition to rickets (2). Indeed, even using present guidelines, too many Americans have low vitamin D blood levels. McCann & Ames propose that, despite uncertainty regarding all of the deleterious effects of vitamin D inadequacy, the evidence overall indicates that supplementation, which is both inexpensive and prudent, is warranted for groups whose vitamin D status is exceptionally low, particularly nursing infants, the elderly, and African Americans (e.g., see (3)).
This review is the fourth in a series by McCann & Ames that critically evaluate scientific evidence linking deficiencies in micronutrients (the approximately 40 vitamins, minerals, amino acids, and fatty acids required for the body to function) to brain function. Other reviews in the series discuss the long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) (4, 5), choline (6), and iron (7).
Could vitamin D, a key milk nutrient, affect how you age?
New study suggests boosting vitamin D may have long-term benefits for inflammation, aging
WASHINGTON, D.C. (November 8, 2007)- There is a new reason for the 76 million baby boomers to grab a glass of milk. Vitamin D, a key nutrient in milk, could have aging benefits linked to reduced inflammation, according to a new study published in the American Journal of Clinical Nutrition.
In a genetic study of more than 2,100 female twin pairs ages 19-79, British and American researchers found that higher vitamin D levels were linked to improved genetic measures of lifelong aging and chronic stress. Using a genetic marker called leukocyte telomere length (LTL), they found those with the highest vitamin D levels had longer LTL, indicating lower levels of inflammation and body stress. The telomere difference between those with the highest and lowest vitamin D levels was equivalent to 5 years of aging.
Previous research has found that shortened LTL is linked to risk for heart disease and could be an indication of chronic inflammation – a key determinant in the biology of aging. While there are several lifestyle factors that affect telomere length (obesity, smoking and lack of physical activity), the researchers noted that boosting vitamin D levels is a simple change to affect this important marker.
Studies continue to link vitamin D to an array of health benefits, securing vitamin D’s “super nutrient” status and providing even more reasons to get adequate amounts of this essential vitamin. Recent research suggests that beyond its well-established role in bone health, vitamin D also may help reduce the risk of certain cancers and autoimmune diseases, such as type 1 diabetes, rheumatoid arthritis and multiple sclerosis.
Milk is a primary source of calcium and vitamin D in the American diet. In fact, government reports indicate that more than 70 percent of the calcium in our nation’s food supply comes from milk and milk products. Additionally, milk is one of the few food sources of vitamin D, which is fast emerging as a “super nutrient.”
The recommended three servings of low fat or fat-free milk provides 900 mg of calcium, 300 IU of vitamin D and 80 mg of magnesium daily.
Study finds no connection between vitamin D and overall cancer deaths
No relationship was found between vitamin D levels and the overall risk of dying from cancer, according to a study published online October 30 in the Journal of the National Cancer Institute. However, higher vitamin D levels were associated with a decreased risk of colorectal cancer death.
Several epidemiological studies have supported the hypothesis that that vitamin D can reduce cancer mortality by decreasing cancer incidence or improving survival. Animal and cell studies suggest that vitamin D may reduce tumor growth and induce cancer cell death. Diet and exposure to sunlight are the major sources of vitamin D.
D. Michal Freedman, Ph.D., of the National Cancer Institute in Bethesda, Md., and colleagues analyzed data from the third national Health and Nutrition Examination Survey to examine the relationship between levels of circulating vitamin D in the blood and cancer mortality in a group of 16,818 participants aged 17 and older.
After about a decade of follow-up, 536 participants had died of cancer. Cancer mortality was not related to the level of circulating vitamin D for the overall group, nor was it related when the researchers looked at the data by sex, race, or age. But higher levels of vitamin D (80 nmol/L or more) were associated with a 72 percent reduced risk of colorectal cancer mortality, compared with lower levels (less than 50 nmol/L).
“To our knowledge, this study is the first to examine the relationship between measured serum vitamin D levels and cancer mortality for selected site and for all sites combined,” the authors write.
In an accompanying editorial, Cindy Davis, Ph.D., and Johanna Dwyer, D.Sc. of the National Institutes of Health in Bethesda, Md., discuss the complicated relationship between nutrients, like vitamin D, and cancer. They suggest that not enough is known about the benefits and limitations of vitamin D to use it for the prevention of disease or death.
“These findings must be put into the context of total diet and lifestyle. There are many risk factors other than diet for colorectal cancer, and there are many possible dietary risk factors other than vitamin D that have been linked to cancer risk,” the editorialists write.
Vitamin D deficiency: Common and problematic yet preventable
In a review article to appear in the July 19th issue of the New England Journal of Medicine, Dr. Michael Holick, an internationally recognized expert in vitamin D, provides an overview of his pioneering work that expounds on the important role vitamin D plays in a wide variety of chronic health conditions, as well as suggesting strategies for the prevention and treatment of vitamin D deficiency.
Humans attain vitamin D from exposure to sunlight, diet and supplements. Vitamin D deficiency is common in children and adults. In utero and childhood, vitamin D deficiency may cause growth retardation, skeletal deformities and increase risk of hip fractures later in life. In adults, vitamin D deficiency may precipitate or exacerbate osteopenia, osteoporosis, muscle weakness, fractures, common cancers, autoimmune diseases, infectious diseases and cardiovascular diseases.
According to Holick, a professor of medicine, physiology, and biophysics, and director of the General Clinical Research Center at Boston University School of Medicine and Director of the Bone Healthcare Clinic at Boston Medical Center, it has been estimated that 1 billion people world-wide are vitamin D deficient or insufficient.
Without vitamin D only about 10-15 percent of dietary calcium and about 60 percent of phosphorus is absorbed by the body. This is directly related to bone mineral density which is responsible for osteoporosis and fractures, as well as muscle strength and falls in adults. In utero and childhood, calcium and vitamin D deficiency prevents the maximum deposition of calcium in the skeleton.
Studies have shown people living at higher latitudes (where the angle of the sun’s rays are unable to sufficiently produce adequate amounts of vitamin D in the skin) are more likely to develop and die of Hodgkin’s lymphoma, colon, pancreatic, prostate, ovarian, breast and other cancers. According to Holick, both prospective and retrospective epidemiologic studies have also shown an association between low levels of vitamin D and an increased risk for Type 1 diabetes, multiple sclerosis, Crohn’s disease, hypertension and cardiovascular disease.
Holick believes the current recommended Adequate Intakes for vitamin D need to be increased to 800 – 1000 IU vitaminD3/d. “However, one can not obtain these amounts from most dietary sources unless one is eating oily fish frequently,” says Holick. “Thus, sensible sun exposure (or UVB irradiation) and/or supplements are required to satisfy the body’s vitamin D requirement,” he adds.
Lastly Holick adds, “The goal of this paper is to make physicians aware of the medical problems associated with vitamin D deficiency. Physicians will then be able to impart this knowledge to their patients so they too will know how to recognize, treat and most importantly, maintain adequate levels of this important vitamin.”
Low Vitamin D = Poor Physical Performance
Older adults who don’t get enough vitamin D – either from their diets or exposure to the sun – may be at increased risk for poor physical performance and disability, according to new research from Wake Forest University School of Medicine and colleagues.__“With a growing older population, we need to identify better ways to reduce the risk of disability,” said lead author Denise Houston, Ph.D. “Our study showed a significant relationship between low vitamin D levels in older adults and poorer physical performance.”__The results are reported in the April issue of the Journal of Gerontology: Medical Sciences.__About one-fourth of people over age 60 have low vitamin D levels. Previous research has shown that vitamin D not only plays a role in bone health, but possibly also in protecting against diabetes, cancer, colds and tuberculosis.__“Recent findings showing the importance of vitamin D status on multiple health outcomes underscore the need for more research on the effects of low vitamin D levels in elderly populations,” said Houston, an instructor in internal medicine - gerontology.__Vitamin D is naturally produced when skin is exposed to the sun’s ultraviolet rays. Foods such as fortified milk, juice and cereals also contain vitamin D, but it is difficult to get enough through diet alone, said Houston.__Older adults are particularly prone to low vitamin D levels because they may get less exposure to sunlight and because their skin is less efficient in producing vitamin D from sun exposure compared to younger adults. Older adults also may not get enough vitamin D from dietary sources.__“There is a growing awareness that the prevalence of low vitamin D levels is common among the elderly,” said Houston.__For the current study, researchers analyzed data from the InCHIANTI study, which evaluated factors contributing to the decline of mobility in late life. The study involved 976 people who were 65 years and older from two towns in the Chianti area of Italy. The mean age of participants was 74.8 years. Data were collected from Sept. 1998 through March 2000.__Participants completed a short physical performance test of their walking speed, ability to stand from a chair and ability to maintain their balance in progressively more challenging positions. In addition, handgrip strength, a predictor of future disability, was measured using a hand-held dynamometer.__The researchers found that physical performance and grip strength were about five to 10 percent lower in those who had low levels of vitamin D. After looking at other variables that could influence the results, such as body mass index, physical activity, the season of the year, mental abilities, health conditions and anemia, the results held true.__The study wasn’t designed to evaluate whether low vitamin D levels actually cause poor physical performance, but the results suggest the need for additional research in this area, said Houston. She said vitamin D plays an important role in muscle function, so it is plausible that low levels of the vitamin could result in lower muscle strength and physical performance.__“But it’s also possible that those with poor physical performance had less exposure to sunlight resulting in low vitamin D levels,” she said.__Current recommendations call for people from age 50 to 69 to get 400 international units (IUs) of vitamin D per day and for those over age 70 to get 600 IUs. Many researchers, however, suggest that higher amounts may be needed.__“Higher amounts of vitamin D may be needed for the preservation of muscle strength and physical function as well as other conditions such as cancer prevention,” said Houston. “The current recommendations are based primarily on vitamin D’s effects on bone health.”__Also see "new-studies-back-vitamin-d-for-cancer prevention":_http://healthnewsreport.blogspot.com/2007/02/2-new-studies-back-vitamin-d-for-cancer.html
Vitamin D supplements appear to be associated with lower risk of death
Individuals who take vitamin D supplements appear to have a lower risk of death from any cause over an average follow-up time of six-years, according to a meta-analysis of 18 previously published studies in the September 10 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Past studies have suggested that deficiencies in vitamin D might be associated with a higher risk of death from cancer, heart disease and diabetes—illnesses that account for 60 percent to 70 percent of deaths in high-income nations, according to background information in the article. “If the associations made between vitamin D and these conditions were consistent, then interventions effectively strengthening vitamin D status should result in reduced total mortality,” the authors write.
Philippe Autier, M.D., of the International Agency for Research on Cancer, Lyon, France, and Sara Gandini, Ph.D., of the European Institute of Oncology, Milano, Italy, searched for randomized controlled trials of vitamin D supplements published before November 2006. They analyzed 18 separate trials that included 57,311 participants and evaluated doses of vitamin D ranging from 300 to 2,000 international units, with an average dose of 528 international units. Most commercially available supplements contain between 400 and 600 international units.
Over an average follow-up period of 5.7 years, 4,777 of the participants died. Individuals who took vitamin D had a 7 percent lower risk of death than those who did not. In the nine trials that collected blood samples, those who took supplements had an average 1.4- to 5.2-fold higher blood level of vitamin D than those who did not.
“Mechanisms by which vitamin D supplementation would decrease all-cause mortality are not clear,” the authors write. Vitamin D could inhibit some mechanisms by which cancer cells proliferate, or it may boost the function of blood vessels or the immune system, they note.
“In conclusion, the intake of ordinary doses of vitamin D supplements seems to be associated with decreases in total mortality rates,” the authors write. “The relationship between baseline vitamin D status, dose of vitamin D supplements and total mortality rates remains to be investigated. Population-based, placebo-controlled randomized trials in people 50 years or older for at least six years with total mortality as the main end point should be organized to confirm these findings.”
Vitamin D Inadequacy May Exacerbate Chronic Pain
Approximately one in four patients who suffer from chronic pain also have inadequate blood levels of vitamin D, possibly contributing to their ongoing pain, according to a new study. Patients lacking sufficient vitamin D also required higher doses of morphine for a longer period of time.
Researchers recorded the serum vitamin D levels of 267 adults undergoing outpatient treatment for chronic pain, as well as their pain medication (morphine) dose and duration of use, and physical and general health functioning.
Of the patients tested, 26 percent had vitamin D inadequacy. Among these patients, the morphine dose was nearly twice that of the group with adequate vitamin D levels. In addition, the vitamin D inadequacy group used morphine for an average of 71.1 months versus 43.8 months. The vitamin D deficient group also reported lower levels of physical functioning and had a poorer view of their overall health.
It has long been known that inadequate levels of vitamin D can cause pain and muscle weakness, according to the study author, W. Michael Hooten, M.D., medical director, and anesthesiologist at Mayo Comprehensive Pain Rehabilitation Center, Rochester, Minnesota. Previous studies also have suggested that pain-related symptoms of vitamin D inadequacy respond poorly to pain medications.
However, “this is the first time that we have established the prevalence of vitamin D inadequacy among a diverse group of chronic pain patients,” Dr. Hooten said.
“The implications are that in chronic pain patients, vitamin D inadequacy is not the principal cause of pain and muscle weakness, however, it could be a contributing but unrecognized factor,” Dr. Hooten said.
Vitamin D inadequacy can be “easily and inexpensively” treated “with essentially no side effects” using a prescription supplement, once or twice a week for four to six weeks, Dr. Hooten said. Further study is needed to determine whether treating inadequate vitamin D levels will result in improvements to the overall general health for patients with chronic pain.
Vitamin D protects cells from stress that can lead to cancer
By inducing a specific gene to increase expression of a key enzyme, vitamin D protects healthy prostate cells from the damage and injuries that can lead to cancer, University of Rochester Medical Center researchers report.
“Many epidemiological studies have suggested the beneficial properties of vitamin D,” said Yi-Fen Lee, associate professor of urology at the Medical Center who led the research. “Our findings reflect what we see in those studies and demonstrate that vitamin D not only can be used as a therapy for prostate cancer, it can prevent prostate cancer from happening.”
The International Journal of Cancer published the findings in its June 15 issue.
Lee and her research team discovered one mechanism involving vitamin D that protects cells from oxidative stress. The vitamin D used in the study is 1,25-hydroxylvitamin D3, the most potent and active form of vitamin D in the human body. Nonmalignant human prostate epithelial cells also were used.
Normal metabolism in cells generates reactive oxygen species (ROS), molecules of peroxide, for example, or so-called free radicals. These substances can play a role in cell signaling and even kill bacteria. Exposure to some chemicals or forms of radiation can produce high levels of ROS that can damage DNA and play a significant role in speeding aging or causing cancer.
Lee found that vitamin D links with a gene known as G6PD, increasing its activity and the production of an enzyme called glucose-6-phosphate dehydrogenase. Increased activity of the enzyme clears cells of ROS, the molecules that can damage and injure cells.
“If you reduce DNA damage, you reduce the risk of cancer or aging,” Lee said. “Our study adds one more beneficial effect of taking a vitamin D supplement. Taking a supplement is especially important for senior citizens and others who might have less circulation of vitamin D, and for people who live and work areas where there is less sunshine.”
Einstein researchers find that vitamin D may protect against peripheral artery disease
(BRONX, NY) – People with low vitamin D levels may face an increased risk for peripheral artery disease (PAD), according to researchers at the Albert Einstein College of Medicine of Yeshiva University. The scientists reported their findings at the American Heart Association’s Arteriosclerosis, Thrombosis and Vascular Biology Annual Conference 2008.
PAD is a common disease that occurs when arteries in the legs become narrowed by fatty deposits, causing pain and numbness and impairing the ability to walk. PAD affects about eight million Americans and is associated with significant disease and death, according to the American Heart Association.
People obtain vitamin D by making it themselves (through skin exposure to sunlight), by ingesting foods such as fish and fortified dairy products that contain vitamin D, or by taking dietary supplements. Adequate vitamin D levels are necessary for bone health, but scientists are only beginning to explore vitamin D’s connection to cardiovascular disease.
“We know that in mice, vitamin D regulates one of the hormone systems that affects blood pressure,” said Dr. Michal Melamed, lead author of the study and assistant professor in the departments of Medicine and Epidemiology & Population Health at Einstein. “Since cells in the blood vessels have receptors for vitamin D, it may directly affect the vessels, although this has not been fully worked out.”
To see whether vitamin D might influence PAD, Dr. Melamed and colleagues analyzed data from a national survey measuring vitamin D levels in the blood of 4,839 U.S. adults. The survey tested these people using the ankle-brachial index, a screening tool for PAD that measures blood flow to the legs. Also measured were other risk factors for PAD such as cholesterol levels, blood pressure and presence of diabetes.
The researchers found that higher levels of vitamin D were associated with a lower prevalence of PAD. Among individuals with the highest vitamin D levels —more than 29.2 nanogram per milliliter (ng/mL) — only 3.7 percent had PAD. Among those with the lowest vitamin D levels — less than 17.8 ng/mL — 8.1 percent had PAD.
When the researchers adjusted for age, sex, race and co-existing health problems, they found that PAD was 64 percent more common in the group with the lowest vitamin D levels compared with the group with the highest levels. For each 10 ng/mL drop in vitamin D level, the risk for PAD increased by 29 percent.
While these findings suggest a role for vitamin D in preventing PAD, Dr. Melamed cautions that they don’t necessarily show that vitamin D truly deserves the credit. It’s possible, she says, that vitamin D levels are a marker for other health practices such as eating a healthy diet. She notes that proving a cause-and-effect relationship between vitamin D and protection against PAD will require a large randomized clinical trial in which some people receive vitamin D supplementation while others do not.
Low Vitamin D Levels Despite Sun Exposure
Vitamin D is often called the “sunshine vitamin” because it is naturally produced by the body when exposed to the Sun’s ultraviolet rays. A new study suggests, however, that even people who receive abundant Sun exposure (nearly 30 hours per week) may still suffer from low serum levels of vitamin D. The researchers measured a form of vitamin D known as 25-hydroxyvitamin, commonly written as 25(OH)D.
“Low vitamin D status is very common and can contribute to the development of osteoporosis and rickets,” said Dr. Neil Binkley of the University of Wisconsin Osteoporosis Clinical Research Program, Madison, and principal author of the study. “Low levels of vitamin D may also play a role in certain cancers, multiple sclerosis, hypertension, and diabetes.”
Researchers conducted a study of 93 adults in Hawaii with self-reported Sun exposure of 28.9 hours per week. Of the 93 participants (30 women and 63 men), 47 (51 percent) had low levels of vitamin D. No correlation was found between serum 25(OH)D and age, lightest or darkest skin color, hours per week of Sun exposure without sunscreen, sun index, total hours of Sun exposure per week, or body mass index (BMI).
The researchers suggest the common clinical recommendation to allow Sun exposure to the hands and face for 15 minutes a day may not assure vitamin D sufficiency.
This paper has been published online and will appear in the June 2007 issue of the Journal of Clinical Endocrinology & Metabolism, a publication of The Endocrine Society.
Aches? Pains? An Extra Dose of Vitamin D May Provide Relief
Pain is the most common complaint leading patients to seek medical care and much of it is chronic, lasting 3 months or longer. According to an extensive review of clinical research in a new report from Pain Treatment Topics, inadequate vitamin D intake has been linked to a long list of chronic painful maladies, including bone and joint pain of various types, muscle pain, fibromyalgia syndrome, rheumatic disorders, osteoarthritis, and other complaints. Lack of vitamin D also has been implicated in the mood disturbances of chronic fatigue syndrome and seasonal affective disorder.
According to Stewart B. Leavitt, MA, PhD, editor of Pain Treatment Topics and author of the report, “our examination of the research, including 22 clinical investigations of patients with various chronic pain and fatigue syndromes, found that these persons almost always had inadequate levels of vitamin D. When sufficient vitamin D supplementation was provided, the aches, pains, weakness, and related problems in most of them either vanished or were at least helped to a significant extent.”
The report, “Vitamin D – A Neglected ‘Analgesic’ for Chronic Musculoskeletal Pain,” was peer-reviewed by a panel of 8 experts and includes the following important points:
>> Vitamin D is a complex nutrient that functions as a hormone to benefit numerous body tissues and organs, including bones, muscles, and nerves.
>> A surprising majority of persons in many parts of the world, including the United States, do not get adequate vitamin D from sun exposure or foods. Why such deficiencies are associated with pain in some persons but not others is not always known.
>> The currently recommended adequate intake of vitamin D – up to 600 IU per day – is outdated and too low. According to the research, most children and adults need at least 1000 IU per day, and persons with chronic musculoskeletal pain would benefit from 2000 IU or more per day of supplemental vitamin D3 (also called cholecalciferol).
>> Vitamin D supplements have a highly favorable safety profile. They interact with very few drugs or other agents, and are usually not harmful unless extremely high doses – such as, 50,000 IU or more – are taken daily for an extended period of time.
>> Vitamin D supplements are easy for patients to self-administer, are well tolerated, and typically cost as little as 7 to 10 cents per day.
Besides the comprehensive *Research Report (50-pages, 170 references), there is available a shorter *Practitioner Briefing (7-pages) that summarizes the report and provides guidance for healthcare providers. Additionally, a special *Patient Brochure (6-pages) explains what vitamin D is, how it works, and how it may help in relieving pain.
*All 3 documents are available for free access at:_http://Pain-Topics.org/VitaminD
In conclusion, Leavitt stresses that vitamin D should not be viewed as a cure for all pain conditions and in all patients. It also is not necessarily a replacement for other pain treatments. “While further research would be helpful,” he says, “current best evidence indicates that recommending supplemental vitamin D for patients with chronic musculoskeletal pain and fatigue disorders would do no harm and could do much good at little cost. It should be considered by healthcare providers for their patients early in the course of pain management.”
Low vitamin D levels associated with death from cardiovascular, all causes
Individuals with lower blood levels of vitamin D appear to have an increased risk of death overall and from cardiovascular causes, according to a report in the June 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
A recent consensus panel estimated that about 50 percent to 60 percent of older individuals in North America and the rest of the world do not have satisfactory vitamin D status, and the situation is similar for younger individuals, according to background information in the article. Blood levels of 25-hydroxyvitamin D, a measure of blood vitamin D levels, lower than 20 to 30 nanograms per milliliter have been associated with falls, fractures, cancer, immune dysfunction, cardiovascular disease and hypertension. These effects are thought to be mediated by the compound 1,25-dihydroxyvitamin D, which is produced by the body and also converted from 25-hydroxyvitamin D.
Harald Dobnig, M.D., of Medical University of Graz, Austria, and colleagues studied 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels in 3,258 consecutive patients (average age 62 years) who were scheduled for coronary angiography testing at a single medical center between 1997 and 2000.
During about 7.7 years of follow-up, 737 (22.6 percent) of participants died, including 463 (62.8 percent) who died of cardiovascular causes. Death rates from any cause and from cardiovascular causes were higher among individuals in the lower one-half of 25-hydroxyvitamin D levels and the lowest one-fourth of 1,25-dihydroxyvitamin D levels. These associations remained when the researchers accounted for other factors, including coronary artery disease, physical activity level and co-occurring diseases.
Low 25-hydroxyvitamin D levels also were correlated with markers of inflammation such as C-reactive protein, as well as signs of oxidative (oxygen-related) damage to cells, the authors note.
"Apart from the proved effects that vitamin D has on bone metabolism and neuromuscular function, appropriate serum levels (that may also be higher than in the present investigation) are associated with a decrease in mortality," they conclude. "Although not proved, it seems possible that at least part of this effect may be due to lowering of a risk profile promoting atherosclerosis [narrowing of the arteries] and preventing cardiovascular end points."
"Based on the findings of this study, a serum 25-hydroxyvitamin D level of 20 nanograms per milliliter or higher may be advised for maintaining general health."
Study Highlights Link Between Vitamin D and Multiple Sclerosis
Vitamin D, the principal regulator of calcium in the body, may prevent the production of malignant cells such as breast and prostate cancer cells and protect against specific autoimmune disorders including multiple sclerosis (MS) according to an article by Sylvia Christakos, PhD, of the UMDNJ-New Jersey Medical School.
In the article, Christakos reports that research shows that the incidence of MS decreases as the amount of vitamin D available to the body increases, either through sunlight exposure or diet. The article notes that MS is “for the most part, unknown in equatorial regions” and that the prevalence of the disease is lower in areas where fish consumption is high. The study is available online in the Journal of Cellular Biochemistry.
“Since vitamin D is produced in the skin through solar or UV irradiation and high serum levels have been shown to correlate with a reduced risk of MS, this suggests that vitamin D may regulate the immune response and may promote a host’s reaction to a pathogen,” Christakos said.
Christakos’ report focuses on the immunosuppressive actions of the active form of vitamin D, which may inhibit the induction of MS, and emphasizes the importance of maintaining a sufficient vitamin D level.
“Evidence has shown that the maintenance of an adequate vitamin D level may have a protective effect in individuals predisposed to MS,” Christakos said. “One device of vitamin D action may be to preserve balance in the T-cell reaction and thus avoid autoimmunity.”
Despite the significant evidence of the benefits of vitamin D relative to MS and other autoimmune diseases, Christakos cautions that further studies are needed to determine whether vitamin D alone or combined with other treatments is effective in individuals with active MS.
Milk nutrients may protect against cancer
New study suggests calcium and vitamin D may reduce cancer risk in women by at least 60 percent
Key milk nutrients, calcium and vitamin D, may do more than just help keep your bones strong. Increasing intake of calcium and vitamin D could reduce the risk for cancer in women by at least 60 percent, according to a new study published in the American Journal of Clinical Nutrition. (1)
The four-year clinical trial included more than one thousand women over the age of 55 in one of three supplement groups: 1) calcium (1400-1500mg) plus vitamin D (1100 IU vitamin D) 2) calcium only (1400-1500 mg) or 3) a placebo. The researchers found that the risk of developing cancer was 60 percent lower for those who took calcium and vitamin D and 47 percent lower for those taking calcium alone, compared to the placebo.
Fifty women developed nonskin cancer through the course of the four-year study, including breast, colon, lung and other cancers. When researchers excluded the 13 cancers diagnosed during first year of the study, determining these cancers were likely present at the study onset, the protective effect of calcium and vitamin D was even greater, with a 77 percent lower risk for cancer for those taking calcium plus vitamin D compared to the placebo.
With an estimated 10.5 million Americans living with cancer, researchers on a quest for new means to prevent or delay the occurrence of this deadly disease are encouraged by these findings.
“This is the first clinical trial to show that boosting vitamin D status can affect the overall risk for cancer – a proposition that has tremendous public health potential,” said lead author Dr Joan Lappe, a nutrition researcher from Creighton University in Omaha. “By choosing vitamin-D rich foods like milk and taking a supplement Americans can help improve their vitamin D levels and potentially impact their cancer risk.”
Milk is the primary source of calcium and an excellent source of vitamin D in the American diet. In fact, government reports indicate that more than 70 percent of the calcium in our nation’s food supply comes from milk and milk products. (2), (3), (4), (5) Additionally, milk is one of the few food sources of vitamin D, which is fast emerging as a “super nutrient.”
Several recent studies have reported similar conclusions, suggesting that calcium and vitamin D may reduce the risk for breast cancer in premenopausal women and colon cancer in older women. (6), (7)Together, these findings give Americans even more reason to meet the recommended three servings of lowfat or fat-free milk each day, providing 900 mg of calcium and 300 IU of vitamin D daily.
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1) Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. American Journal of Clinical Nutrition. 2007;85:1586-1591.
2) Gerrior S, Bente L, Hiza, H. (2004). Nutrient Content of the U.S. Food Supply, 1909-2000. (Home Economics Research Report No. 56). U.S. Department of Agriculture, Center for Nutrition Policy and Promotion.
3) Dietary Guidelines for Americans 2005, U.S. Department of Agriculture, www.healtheirus.gov/dietaryguidelines.
4) Cotton PA, Subar AF, Friday JE, Cook A. Dietary sources of nutrients among US adults, 1994 to 1996. Journal of the American Dietetic Association. 2004; 104:921-930.
5) Weinberg L, Berner LA, Groves JE. Nutrient contributions of dairy foods in the United States, Continuing Survey of Food Intakes by Individuals, 1994-1996, 1998. Journal of the American Dietetic Association. 2004; 104:895-902.
6) Lin J, Manson JE, Lee I, Cook NR, Buring JE, Zhang SM. Intakes of Calcium and Vitamin D and Breast Cancer Risk in Women. Archives of Internal Medicine. 2007;167:1050-1059.
7) Feskanich D, Ma J, Fuchs CS, Kirkner GJ, Hankinson SE, Hollis BW, Giovannucci EL. Plasma vitamin D metabolites and risk of colorectal cancer in women. Cancer Epidemiology Biomarkers and Prevention. 2004;13:1502-1508.
An adequate amount of Vitamin D is known to improve bone density, but the impact goes much further than bone strength; Vitamin D deficiency can impact nearly all of the body’s functions. This topic will be investigated at the American Association of Clinical Endocrinologists (AACE) 17th Annual Meeting & Clinical Congress, on Thursday, May 15, 2008, at the Walt Disney World Dolphin Resort in Orlando.
“Vitamin D plays an important role in most of the body’s tissues,” Robert P. Heaney, FACP, FACN said. “Despite its vast importance in the human body, most people don’t receive enough.”
Vitamin D deficiency can manifest itself in a variety of different forms, depending on a person’s genetic makeup. It can result in impaired bone mineralization, and leads to bone softening diseases like rickets in children and osteomalacia in adults, and is a possible contributor to osteoporosis.
Although many are familiar with the importance of Vitamin D in bones, evidence shows that Vitamin D may be associated with diabetes, hypertension, multiple sclerosis, infectious diseases, and even cancer.
Fight Off Aches & Pains This Winter With Extra Vitamin D
It’s no wonder many people feel achy and sore, and sometimes tired and depressed, during winter months – they’re often not getting enough vitamin D. The body makes vitamin D from the sun’s ultraviolet rays, so it’s known as the sunshine vitamin, but this source is in short supply throughout late fall and winter.
According to an extensive review of clinical research in a report from Pain Treatment Topics (http://Pain-Topics.org), inadequate vitamin D has been linked to a long list of painful maladies, including bone and joint pain, muscle aches, fibromyalgia syndrome, rheumatic disorders, osteoarthritis, and other complaints. Lack of vitamin D also has been implicated in the mood disturbances of chronic fatigue syndrome and seasonal affective disorder, or SAD, which are more common during winter.
Author of the report and editor of Pain Treatment Topics, Stewart B. Leavitt, MA, PhD, notes that for many people sunshine is not an ample source of vitamin D during most of the year and the few foods containing the vitamin do not provide enough of it. “In our review of 22 clinical research studies persons with various pain and fatigue syndromes almost always lacked vitamin D, especially during winter months. When sufficient vitamin D supplementation was provided, the aches, pains, weakness, and related problems in most sufferers either vanished or were at least helped to a significant degree.”
The report mentions the following important points:
>> Vitamin D is a complex nutrient that actually functions as a hormone to benefit numerous body tissues and organs, including bones, muscles, and nerves.
>> A surprising majority of persons in many parts of the world, including the United States, do not get enough vitamin D from sunshine or foods.
>> The currently recommended adequate intake of vitamin D – up to 400 IU per day in children and 600 IU per day in adults – is outdated and too low. According to the research, most children and adults need at least 1000 IU per day, and persons with bone or muscle aches and pains could benefit from 2000 IU or more per day of supplemental vitamin D3 (also called cholecalciferol), especially during winter months.
>> Vitamin D supplements are generally safe if taken as directed. They interact with very few drugs or other agents, and are usually not harmful unless very high daily doses – such as, 50,000 IU or more – are taken for an extended period of time.
>> Vitamin D supplements are easy to take, usually have no side effects, and typically cost as little as 7 to 10 cents per day.
Besides the comprehensive **Research Report (50-pages, 170 references) -- titled “Vitamin D – A Neglected ‘Analgesic’ for Chronic Musculoskeletal Pain” -- there is available a shorter **Practitioner Briefing (7-pages) that summarizes the report and provides guidance for healthcare providers. Additionally, a special **Patient Brochure (6-pages) explains what vitamin D is, how it works, and how it can help in relieving aches and pains.
**All 3 documents are available for free access at:_http://pain-topics.org/vitamind
In conclusion, Leavitt stresses that vitamin D should not be viewed as a cure for all pain conditions, and it is not necessarily a replacement for other pain-relief treatments. “While further research would be helpful,” he says, “extra vitamin D should be considered for all persons in late fall or early winter, and especially for those who have developed aches and pains, or fatigue and mood disorders.”
'LET THE SUNSHINE IN' TO PROTECT YOUR HEART THIS WINTER
Loyola Researchers Find Sunshine Deficit May Diminish Vitamin D Levels and Harm Cardiovascular Health
MAYWOOD - The temperature might not be the only thing plummeting this winter. Many people also will experience a decrease in their vitamin D levels, which can play a role in heart disease, according to a new review article in Circulation.
Vitamin D deficiency results in part from reduced exposure to sunlight, which is common during cold weather months when days are shorter and more time is spent indoors.
"Chronic vitamin D deficiency may be a culprit in heart disease, high blood pressure and metabolic syndrome," said Sue Penckofer, PhD, RN, study author and professor, Marcella Niehoff School of Nursing, Loyola University Chicago.
The review article cited a number of studies that linked vitamin D deficiency to heart disease. These studies found rates of severe disease or death may be 30 to 50 percent higher among sun-deprived individuals with heart disease.
Penckofer and colleagues concluded that diet alone is not sufficient to manage vitamin D levels. Treatment options to correct this level, such as vitamin D2 or D3, may decrease the risk of severe disease or death from cardiovascular disorders. The preferred range in the body is 30 - 60 ng/mL of 25(OH) vitamin D.
"Most physicians do not routinely test for vitamin D deficiency," said Penckofer. "However, most experts would agree that adults at risk for heart disease and others who experience fatigue joint pain or depression should have their vitamin D levels measured."
Study authors also included Glen W. Sizemore, MD, emeritus professor of Medicine, Division of Endocrinology and Metabolism, Loyola University Chicago Stritch School of Medicine, and Diane E. Wallis, MD, Midwest Heart Specialists, Downers Grove, Ill.
Study helps clarify role of vitamin D in cancer therapy
A colon cancer cell isn't a lost cause. Vitamin D can tame the rogue cell by adjusting everything from its gene expression to its cytoskeleton. In the Nov. 17 issue of the Journal of Cell Biology, Ordóñez-Morán et al. show that one pathway governs the vitamin's diverse effects. The results help clarify the actions of a molecule that is undergoing clinical trials as a cancer therapy.
Vitamin D stymies colon cancer cells in two ways. It switches on genes such as the one that encodes E-cadherin, a component of the adherens junctions that anchor cells in epithelial layers. The vitamin also induces effects on the cytoskeleton that are required for gene regulation and short-circuiting the Wnt/b-catenin pathway, which is overactive in most colon tumors. The net result is to curb division and prod colon cancer cells to differentiate into epithelial cells that settle down instead of spreading.
To delve into the mechanism, the team dosed colon cancer cells with calcitriol, the metabolically active version of vitamin D. Calcitriol triggered a surge of calcium into the cells and the subsequent switching on of RhoA–RhoGTPases, which have been implicated in the cytoskeletal changes induced by vitamin D. The activated RhoA in turn switched on one of its targets, the rho-associated coiled kinase (ROCK), which then roused two other kinases. Each step in this nongenomic pathway was necessary to spur the genomic responses, the researchers showed. The team also nailed down the contribution of the vitamin D receptor (VDR). The receptor was crucial at the beginning of the pathway, where it permitted the calcium influx, and at the end, where it activated and repressed genes.
The study is the first to show that vitamin D's genomic and nongenomic effects integrate to regulate cell physiology. One question the researchers now want to pursue is whether VDR from different locations—the nucleus, the cytosol, and possibly the cell membrane—has different functions in the pathway.
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