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.
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.