New research is published so frequently on topics that I have written about only recently that I have a hard time keeping up. Here are updates on newly published research on alcohol, apples, aspirin, caffeine dark chocolate, exercise, fish, green tea, oatmeal, red wine and Vitamin D
Moderate Alcohol Consumption May Help Seniors Keep Disabilities at Bay
It is well known that moderate drinking can have positive health benefits — for instance, a couple of glasses of red wine a day can be good for the heart. But if you're a senior in good health, light to moderate consumption of alcohol may also help prevent the development of physical disability.
That's the conclusion of a new UCLA study, available in the online edition of the American Journal of Epidemiology, which found that light to moderate drinking among these seniors reduced their odds of developing physical problems that would prevent them from performing common tasks such as walking, dressing and grooming.
"If you start out in good health, alcohol consumption at light to moderate levels can be beneficial," said lead study author Dr. Arun Karlamangla, an associate professor of medicine in the division of geriatrics at the David Geffen School of Medicine at UCLA. "But if you don't start out healthy, alcohol will not give you a benefit."
The researchers based their study on data from three waves of the National Health and Nutrition Examination Survey's Epidemiologic Follow-up Study (1982–84, 1987 and 1992). The sample, which included 4,276 people split evenly between male and female, was about 92 percent white, with a mean age of 60.4 years.
Drinkers were classified as light to moderate if they consumed less than 15 drinks per week and less than five drinks per drinking day (less than four per day for women). Heavy drinkers were those who consumed 15 or more drinks per week or five or more per drinking day (four or more for women). Abstainers were those who drank fewer than 12 alcoholic beverages the previous year.
Having a physical disability means having trouble performing, or being unable to perform, routine tasks such as dressing and grooming, personal hygiene, arising, eating, walking, gripping, reaching, and doing daily errands and chores. Participants were asked if they experienced no difficulty, some difficulty, much difficulty or were unable to do these activities at all when alone and without the use of aids.
At the start of the survey, 32 percent of men and 51 percent of women abstained from drinking, 51 percent of men and 45 percent of women were light to moderate drinkers, and 17 percent of men and 4 percent women were heavy drinkers.
No one had any disabilities at the outset, but 7 percent died and 15 percent became disabled over five years.
The researchers found that light to moderate drinkers in good health had a lower risk for developing new disabilities, compared with both abstainers and heavy drinkers.
In unadjusted analyses, light to moderate drinkers had a 17.7 percent chance of becoming disabled or dying in five years, compared with 26.7 percent for abstainers and 21.4 percent for heavy drinkers. Among survivors, the risk for new disability was 12.5 percent for light to moderate drinkers, compared with 20 percent for abstainers and 15.6 percent for heavy drinkers.
However, after controlling for confounding variables such as age, smoking, exercise, heart attacks and strokes, the benefits of alcohol consumption were seen only in seniors who rated their health as good or better: There was a 3 to 8 percent reduction in the odds of developing disability with each additional drink per week in older men and women in good or better health who were not heavy drinkers, but there was no such benefit seen in those who rated their health as fair or poor.
"Light to moderate alcohol consumption appears to have disability prevention benefits only in men and women in relatively good health," the researchers wrote. "It is possible that those who report poor health have progressed too far on the pathway to disability to accrue benefits from alcohol consumption and that alcohol consumption may even be deleterious for them."
New study provides further evidence that apple juice can delay onset of Alzheimer's disease
A growing body of evidence demonstrates that we can take steps to delay age-related cognitive decline, including in some cases that which accompanies Alzheimer's disease, according to a study published in the January 2009 issue of the Journal of Alzheimer's Disease.
Thomas B. Shea, PhD, of the Center for Cellular Neurobiology; Neurodegeneration Research University of Massachusetts, Lowell and his research team have carried out a number of laboratory studies demonstrating that drinking apple juice helped mice perform better than normal in maze trials, and prevented the decline in performance that was otherwise observed as these mice aged.
In the most recent study Shea and his team demonstrated that mice receiving the human equivalent of 2 glasses of apple juice per day for 1 month produced less of a small protein fragment, called "beta-amyloid" that is responsible for forming the "senile plaques" that are commonly found in brains of individuals suffering from Alzheimer's disease.
Dr. Shea commented that "These findings provide further evidence linking nutritional and genetic risk factors for age-related neurodegeneration and suggest that regular consumption of apple juice can not only help to keep one's mind functioning at its best, but may also be able to delay key aspects of Alzheimer's disease and augment therapeutic approaches."
The article is "Dietary Supplementation with Apple Juice Decreases Endogenous Amyloid-_ Levels in Murine Brain" by Amy Chan and Thomas B. Shea. It is published in the Journal of Alzheimer's Disease 16:1 (January 2009).
Aspirin can prevent liver damage that afflicts millions, Yale study finds
Simple aspirin may prevent liver damage in millions of people suffering from side effects of common drugs, alcohol abuse, and obesity-related liver disease, a new Yale University study suggests.
The study in the January 26 edition of Journal of Clinical Investigation documents that in mice, aspirin reduced mortality caused by an overdose of acetaminophen, best known by the brand name Tylenol. It further showed that a class of molecules known as TLR antagonists, which block receptors known to activate inflammation, have a similar effect as aspirin. Since these agents seem to work by reducing injury-induced inflammation, the results suggest aspirin may help prevent and treat liver damage from a host of non-infectious causes, said Wajahat Mehal, M.D., of the Section of Digestive Diseases and Department of Immunobiology at Yale School of Medicine.
"Many agents such as drugs and alcohol cause liver damage, and we have found two ways to block a central pathway responsible for such liver injury," Mehal said. "Our strategy is to use aspirin on a daily basis to prevent liver injury, but if it occurs, to use TLR antagonists to treat it."
Promising drugs that have failed clinical trials because of liver toxicity might be resurrected if combined with aspirin, Mehal said.
"This offers the exciting possibility of reducing a lot of pain and suffering in patients with liver diseases, using a new and very practical approach," Mehal said.
Caffeine: Energy drinks: The coffee of a new generation?
Universite de Montreal nutritionist warns of the dangers of energy drinks
It's not uncommon for students to consume energy drinks to increase their concentration as they study throughout the night. "Energy drinks are the coffee of a new generation," says Stéphanie Côté, nutritionist with Extenso, a Université de Montréal health and nutrition think-tank. "These drinks are made up of sugar and caffeine and can have a negative impact on health."
According to a 2008 report by Agriculture and Agri-Food Canada, 1.5 billion cans of Red Bull were sold in the United States in 2004. Consumption in Canada is said to be comparable and it is a growing trend for 18-to 24-year-olds. This market segment is broadening as younger children are beginning to consume these drinks before doing physical activity.
But these drinks aren't recommended to either athletes or children under the age of 12. "Energy drinks don't hydrate the body efficiently," says Côté. "Because they have too much sugar. And caffeine doesn't necessarily improve physical performance. In high quantities it can increase the risks of fatigue and dehydration."
Several studies have demonstrated that strong doses of caffeine can increase hypertension, cause heart palpitations, provoke irritability and anxiety as well as cause headaches and insomnia. Health Canada does not recommend consuming more than two cans per day.
But many young people do not respect this warning. Furthermore, close to 50 percent of 18 to 24-year-olds claim to consume energy drinks mixed with alcohol. Vodka Red Bulls are in vogue despite warnings against the mix.
"Usually when someone consumes too much alcohol, their head spins and they feel tired. Energy drinks cancel out these warning signs," explains Côté. "The person feels good and therefore keeps drinking without realizing they are drunk
Dark chocolate is most filling
We have known for a long time that it is healthier to eat dark chocolate, but now scientists at the Department of Human Nutrition at LIFE, University of Copenhagen, have found that dark chocolate also gives more of a feeling of satiety than milk chocolate.
To compare the effects of dark and milk chocolate on both appetite and subsequent calorie intake, 16 young and healthy men of normal weight who all liked both dark and milk chocolate took part in a so-called crossover experiment. This meant that they reported for two separate sessions, the first time testing the dark chocolate, and the second time the milk chocolate.
They had all fasted for 12 hours beforehand and were offered 100g of chocolate, which they consumed in the course of 15 minutes. The calorific content was virtually the same for the milk and dark chocolate.
During the following 5 hours, participants were asked to register their appetite every half hour, i.e. their hunger, satiety, craving for special foods and how they liked the chocolate.
Two and a half hours after eating the chocolate, participants were offered pizza ad lib.
They were instructed to eat until they felt comfortably satiated. After the meal, the individuals’ calorie intake was registered.
The results were significant. The calorie intake at the subsequent meal where they could eat as much pizza as they liked was 15 per cent lower when they had eaten dark chocolate beforehand.
The participants also stated that the plain chocolate made them feel less like eating sweet, salty or fatty foods.
So apart from providing us with the healthier fatty acids and many antioxidants, dark chocolate can now also help us steer clear of all the sweet, salty and fattening Christmas foods.
Exercise, Calcium-Rich Diet Could Cut Risk of Metabolic Syndrome
Adopting daily exercise sessions and a calcium-rich diet could reduce the risk of a group of health risk factors called the metabolic syndrome, finds a new study of Illinois adults.
Metabolic syndrome is a cluster of symptoms — large abdominal girth, high blood pressure, high cholesterol levels and insulin insensitivity — that together signal a significantly higher risk for heart disease and type 2 diabetes.
“As with many health conditions, when the good behaviors are absent, the condition is more prevalent,” said Adam Reppert, lead study author.
Reppert is a clinical dietitian at Swedish Covenant Hospital in Chicago. The study appears in the November/December issue of the American Journal of Health Promotion.
In a 2005 telephone survey, 5,077 Illinois adults provided information about chronic health conditions, exercise habits and their intake of fruit, vegetables and other sources of calcium.
Researchers then identified respondents with the condition.
“We found that metabolic syndrome was more prevalent in the older, less affluent population, in people with less education and in those who engaged in less physical activity, consumed calcium-rich foods less frequently and had hypertension and hypercholesterolemia,” Reppert said.
In Illinois residents, just over 16 percent had the condition, lower than national estimates of 23.7 percent to 34.5 percent. Although national studies found a greater prevalence of the condition among Hispanics and whites, this study found the syndrome to be significantly more prevalent among blacks than whites or Hispanics.
Health behaviors also appeared to have a significant influence. The researchers found that adults who reported little or no daily exercise had nearly twice the risk of developing the condition.
In addition, adults who failed to consume calcium-rich foods regularly had about 1.5 times the risk of developing metabolic syndrome, compared to adults who ate calcium-rich diets.
“There are a lot of papers out there about the development of metabolic syndrome,” said Steve Haffner, a professor in the department of medicine at the University of Texas Health Science Center at San Antonio. What’s new and potentially useful is the authors’ finding of a higher prevalence in lower-income, lower-education households, according to Haffner, who was not involved with the study.
For those with metabolic syndrome, a diagnosis does not mean they are destined for diabetes or heart disease. Rather, it is an opportunity for patients “to intervene to prevent heart disease or diabetes, because once you have those things they are irreversible, although manageable,” Reppert said.
Exercise helps prevent age-related brain changes in older adults
Older adults who exercise regularly show increased cerebral blood flow and a greater number of small blood vessels in the brain, according to findings presented at the annual meeting of the Radiological Society of North America (RSNA).
The study, conducted at the University of North Carolina (UNC) – Chapel Hill, is the first to compare brain scans of older adults who exercise to brain scans of those who do not.
"Our results show that exercise may reduce age-related changes in brain vasculature and blood flow," said presenter Feraz Rahman, M.S., currently a medical student at Jefferson Medical College in Philadelphia. "Other studies have shown that exercise prevents cognitive decline in the elderly. The blood vessel and flow differences may be one reason."
The researchers recruited 12 healthy adults, age 60 to 76. Six of the adults had participated in aerobic exercise for three or more hours per week over the last 10 years, and six exercised less than one hour per week. All of the volunteers underwent MRI to determine cerebral blood flow and MR angiography to depict blood vessels in the brain.
Using a novel method of three-dimensional (3-D) computer reconstruction developed in their lab, the researchers were able to make 3-D models of the blood vessels and examine them for shape and size. They then compared the blood vessel characteristics and how they related to blood flow in both the active and inactive groups.
The results showed that the inactive group exhibited fewer small blood vessels in the brain, along with more unpredictable blood flow through the brain.
"The active adults had more small blood vessels and improved cerebral blood flow," said the study's senior author, J. Keith Smith, M.D., Ph.D., associate professor of radiology at UNC School of Medicine. "These findings further point out the importance of regular exercise to healthy aging."
Aerobic exercise is better at suppressing appetite than non-aerobic exercise
A vigorous 60-minute workout on a treadmill affects the release of two key appetite hormones, ghrelin and peptide YY, while 90 minutes of weight lifting affects the level of only ghrelin, according to a new study. Taken together, the research shows that aerobic exercise is better at suppressing appetite than non-aerobic exercise and provides a possible explanation for how that happens.
This line of research may eventually lead to more effective ways to use exercise to help control weight, according to the senior author, David J. Stensel of Loughborough University in the United Kingdom.
The study, “The influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin and peptide YY in healthy males,” appears in the online edition of the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, published by The American Physiological Society. The authors are David R. Broom, James A. King and David J. Stensel of Loughborough University, and Rachel L. Batterham of University College, London.
Treadmill versus weight lifting
There are several hormones that help regulate appetite, but the researchers looked at two of the major ones, ghrelin and peptide YY. Ghrelin is the only hormone known to stimulate appetite. Peptide YY suppresses appetite.
Ghrelin was discovered by researchers in Japan only about 10 years ago and was originally identified for its role as a growth hormone. Only later did its role in stimulating appetite become known. Peptide YY was discovered less than 25 years ago.
In this experiment, 11 male university students did three eight-hour sessions. During one session they ran for 60 minutes on a treadmill, and then rested for seven hours. During another session they did 90 minutes of weight lifting, and then rested for six hours and 30 minutes. During another session, the participants did not exercise at all.
During each of the sessions, the participants filled out surveys in which they rated how hungry they felt at various points. They also received two meals during each session. The researchers measured ghrelin and peptide YY levels at multiple points along the way.
They found that the treadmill (aerobic) session caused ghrelin levels to drop and peptide YY levels to increase, indicating the hormones were suppressing appetite. However, a weight-lifting (non-aerobic) session produced a mixed result. Ghrelin levels dropped, indicating appetite suppression, but peptide YY levels did not change significantly.
Based on the hunger ratings the participants filled out, both aerobic and resistance exercise suppressed hunger, but aerobic exercise produced a greater suppression of hunger. The changes the researchers observed were short term for both types of exercise, lasting about two hours, including the time spent exercising, Stensel reported.
“The finding that hunger is suppressed during and immediately after vigorous treadmill running is consistent with previous studies indicating that strenuous aerobic exercise transiently suppresses appetite,” Stensel said. “The findings suggest a similar, although slightly attenuated response, for weight lifting exercise.”
Focus on active ghrelin
Previous studies have been inconclusive about whether exercise decreases ghrelin levels, but this study may help explain those mixed results, according to the researchers.
Ghrelin comes in two forms, acylated and non-acylated. The researchers measured acylated ghrelin, also called active ghrelin, because it can cross the blood-brain barrier and reach the appetite center in the brain. Stensel suggests that future research concentrate on active ghrelin.
While the study showed that exercise suppresses appetite hormones, the next step is to establish whether this change actually causes the suppression of eating.
Exercise and rest reduce cancer risk
Exercise is good for more than just your waistline. A recent study presented at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research suggests that regular physical activity can lower a woman's overall risk of cancer – but only if she gets a good night's sleep. Otherwise, lack of sleep can undermine exercise's cancer prevention benefits.
"Greater participation in physical activity has consistently been associated with reduced risk of cancer incidence at several sites, including breast and colon cancers," said James McClain, Ph.D., cancer prevention fellow at the National Cancer Institute and lead author of the study. "Short duration sleep appears to have opposing effects of physical activity on several key hormonal and metabolic parameters, which is why we looked at how it affected the exercise/cancer risk relationship."
Even though the exact mechanism of how exercise reduces cancer risk isn't known, researchers believe that physical activity's effects on factors including hormone levels, immune function, and body weight may play an important role. The study examined the link between exercise and cancer risk, paying special attention to whether or not getting adequate sleep further affected a women's cancer risk.
Researchers assessed the association between physical activity energy expenditure (PAEE), sleep duration and incidence of overall, breast, and colon cancer in 5,968 women at least 18 years old with no previous cancer diagnoses. The women completed an initial survey in 1998 and were then tracked through the Washington County Cancer Registry and Maryland State Cancer Registry for nearly 10 years.
The results pointed to a sleep-exercise link. "Current findings suggest that sleep duration modifies the relationship between physical activity and all-site cancer risk among young and middle-aged women," he said.
Out of those 5,968 women, 604 experienced a first incidence of cancer, including 186 breast cancer cases. Women in the upper 50 percent of PAEE showed significantly reduced risk of overall cancer and breast cancer. Among women 65 or younger when surveyed and in the upper half of PAEE, sleeping less than seven hours a day increased overall cancer risk, negating much of the protective effects of physical activity on cancer risk for this group.
The next step, says McClain, would be to confirm current findings and investigate potential mechanisms underlying the interaction between sleep and exercise in order to better understand their roles in cancer prevention.
Research is expanding rapidly on the effect of insufficient and prolonged sleep duration on many health outcomes although few studies have examined the association of sleep duration with cancer risk. This novel study examining the interaction of sleep and physical activity suggests another future focus of research on health behaviors and cancer outcomes.
Exercise increases brain growth factor and receptors, prevents stem cell drop in middle age
A new study confirms that exercise can reverse the age-related decline in the production of neural stem cells in the hippocampus of the mouse brain, and suggests that this happens because exercise restores a brain chemical which promotes the production and maturation of new stem cells.
Neural stem cells and progenitor cells differentiate into a variety of mature nerve cells which have different functions, a process called neurogenesis. There is evidence that when fewer new stem or progenitor cells are produced in the hippocampus, it can result in impairment of the learning and memory functions. The hippocampus plays an important role in memory and learning.
The study, "Exercise enhances the proliferation of neural stem cells and neurite growth and survival of neuronal progenitor cells in dentate gyrus of middle-aged mice," was carried out by Chih-Wei Wu, Ya-Ting Chang, Lung Yu, Hsiun-ing Chen, Chauying J. Jen, Shih-Ying Wu, Chen-Peng Lo, Yu-Min Kuo, all of the National Cheng Kung University Medical College in Taiwan. The study appears in the November issue of the Journal of Applied Physiology, published by The American Physiological Society.
Regular sprint boosts metabolism
A regular high-intensity, three-minute workout has a significant effect on the body's ability to process sugars. Research published in the open access journal BMC Endocrine Disorders shows that a brief but intense exercise session every couple of days may be the best way to cut the risk of diabetes.
Professor James Timmons worked with a team of researchers from Heriot-Watt University Edinburgh, Scotland, to investigate the effect of 'high-intensity interval training' (HIT) on the metabolic prowess of sixteen sedentary male volunteers. He said, "The risk of developing cardiovascular disease and type two diabetes is substantially reduced through regular physical activity. Unfortunately, many people feel they simply don't have the time to follow current exercise guidelines. What we have found is that doing a few intense muscle exercises, each lasting only about 30 seconds, dramatically improves your metabolism in just two weeks."
Current exercise guidelines suggest that people should perform moderate to vigorous aerobic and resistance exercise for several hours per week. While these guidelines are very worthwhile in principle, Timmons suggests that a lack of compliance indicates the need for an alternative, "Current guidelines, with regards to designing exercise regimes to yield the best health outcomes, may not be optimal and certainly require further discussion. The low volume, high intensity training utilized in our study substantially improved both insulin action and glucose clearance in otherwise sedentary young males and this indicates that we do not yet fully appreciate the traditional connection between exercise and diabetes".
The subjects in this trial used exercise bikes to perform a quick sprint at their highest possible intensity. In principle, however, any highly vigorous activity carried out a few days per week should achieve the same protective metabolic improvements. Timmons added, "This novel approach may help people to lead a healthier life, improve the future health of the population and save the health service millions of pounds simply by making it easier for people to find the time to exercise".
Special Report on Lifelong Exercise, a supplement to the February issue of Mayo Clinic Health Letter.
Age can exact a toll on the body as muscles weaken and bones become more brittle. But a well-rounded fitness program with five components -- aerobics, strength training, core stability, balance and flexibility -- can help counter the effects of aging. Talk to your doctor before starting any exercise program.
Regular aerobic activity improves the body’s use of oxygen and is important for cardiovascular health. Walking, biking, dancing and other activities can be aerobic exercise, depending on the intensity. A good starter goal is 30 to 60 minutes of aerobic activity at least three days a week, working up to five days a week.
Strength training uses free weights, body weight, resistance bands or weight-resistance machines to increase muscle strength and endurance. Strength training two to three times a week for 20 to 30 minutes is sufficient for most people. Improvements should be noticeable within weeks.
Core stability training, part of strength training, focuses on the areas around the trunk. A strong core increases balance and combats poor posture and back pain. Pilates workouts, a low-impact fitness technique, or balanced sitting on a large fitness ball are examples of ways to increase core stability. Technique is important; to get started, working with a trainer may be beneficial.
Almost any activity that requires movement can help balance. And, balance exercise can be incorporated into strength training by adding variations such as standing on one leg or using a weight in only one hand. Poor balance is a major cause of falls that result in fractures and disability.
Flexibility can be maintained or improved with regular stretching. It’s a good idea to stretch for five to 10 minutes before and after workouts. A trainer, doctor or physical therapist can suggest exercises to maintain and increase flexibility.
Other highlights of the report, which covers the benefits of exercise and how to get started and stick with a program, include:
-- Regular physical activity, for example, gardening or walking the dog, is beneficial. But a planned structured exercise program, such as swimming laps, taking brisk walks or lifting weights, yields greater rewards.
-- While small amounts of exercise -- as little as 10 minutes at a time -- can be beneficial, more is needed to achieve greater health improvements. The federal government’s Physical Activity Guidelines for Americans recommends at least 150 minutes of moderate intensity or 75 minutes of vigorous intensity activity a week for basic health benefits. For greater benefits, adults should aim for 300 minutes of moderate activity or 150 minutes of vigorous activity a week, according to the guidelines. Moderate activity includes brisk walking, water aerobics, ballroom dancing, doubles tennis or biking on level ground. Vigorous activity includes jogging, running, aerobic dancing, swimming laps, singles tennis and cycling faster than 10 miles an hour.
-- The payoffs can be plentiful. Exercise helps prevent cardiovascular disease, high blood pressure, osteoporosis, obesity, diabetes and some cancers. Exercise boosts the immune system, increases energy and improves sleep. It also increases life expectancy and helps people maintain independence as they age.
Taking Fish Oil Supplements
Do fish oil supplements just seem too … well … fishy?
The February issue of Mayo Clinic Health Letter explains some health benefits of this diet supplement and ways to overcome the occasional fishy aftertaste.
Fish oil supplements are especially good for those who want the heart health benefits of omega-3 fatty acids but don’t like to eat fish. Fish oil supplements often are prescribed for heart attack survivors; the supplements can help prevent future heart problems. They also are prescribed for people with high triglycerides, a type of fat in the blood.
Tips to avoid fishy aftertaste or burps include:
-- Swallow the capsule frozen. This slows the breakdown of fish oil in the stomach, often reducing fishy burps. The fish oil is still digested effectively.
-- Take the capsule at the beginning of a meal. Food traps the fish oil in the stomach, and mixing buffers the odor.
Try an “odorless” supplement. This type of coated capsule passes through the stomach and dissolves in the intestines.
Switch brands. A different brand may taste less fishy. For fish oil purists, some manufacturers make a pure omega-3 fatty acids product that doesn’t taste fishy, although it is likely to cost more than standard products.
Fish: Research Shows Novel Benefits of Fatty Acids in Arteries
New research from Columbia University Medical Center continues to shed light on the benefits of making fish a staple of any diet.
Fish are generally rich in omega-3 fatty acids, which have shown benefit in many health areas such as helping to prevent mental illness and delaying some of the disabilities associated with aging. Eating tuna, sardines, salmon and other so-called cold water fish appears to protect people against clogged arteries. Omega-3 fatty acids can also lower triglycerides, a type of fat often found in the bloodstream.
Now, a CUMC research team led by Richard J. Deckelbaum, M.D., Director of the Columbia Institute of Human Nutrition, has found that a diet rich in fish oils can prevent the accumulation of fat in the aorta, the main artery leaving the heart. The beneficial actions of fish oil that block cholesterol buildup in arteries are even found at high fat intakes.
The study was conducted in three separate populations of mice: one that was fed a balanced diet, one that was fed a diet resembling a “Western” diet high in saturated fat, and a third that was fed a high fish fat diet rich in omega-3 fatty acids.
Researchers in Dr. Deckelbaum’s laboratory, including Chuchun Liz Chang, a Ph.D. student in nutritional and metabolic biology, found that the fatty acids contained in fish oil markedly inhibit the entry of “bad,” or LDL, cholesterol into arteries and, as a result, much less cholesterol collects in these vessels.
They found that this is related to the ability of those fatty acids to markedly decrease lipoprotein lipase, a molecule that traps LDL in the arterial wall. This will likely prove to be important as a new mechanism which helps explain benefits of omega-3 fatty acids on heart health.
Dr. Deckelbaum advises those interested in increasing omega-3 intakes do so by either increasing fish intake or by using supplements that contain the “long-chain” fatty acids, EPA and DHA, which are found in cold water fish.
The research was published February 5, 2009 by the American Heart Association’s Arteriolosclerosis, Thrombosis and Vascular Biology, and is supported in part by grants from the National Institutes of Health.
Green tea may delay onset of type 1 diabetes
A powerful antioxidant in green tea may prevent or delay the onset of type 1 diabetes, Medical College of Georgia researchers say.
Researchers were testing EGCG, green tea's predominant antioxidant, in a laboratory mouse with type 1 diabetes and primary Sjogren's syndrome, which damages moisture-producing glands, causing dry mouth and eyes.
"Our study focused on Sjogren's syndrome, so learning that EGCG also can prevent and delay insulin-dependent type 1 diabetes was a big surprise," says Dr. Stephen Hsu, molecular/cell biologist in the School of Dentistry.
They found it also worked well in their original disease focus.
In the mouse, EGCG reduced the severity and delayed onset of salivary gland damage associated with Sjogren's syndrome, which has no known cure.
"EGCG modulates several important genes, so it suppresses the abnormality at the molecular level in the salivary gland. It also significantly lowered the serum autoantibodies, reducing the severity of Sjogren's syndrome-like symptoms," Dr. Hsu says. Autoantibodies are antibodies the body makes against itself.
Both type 1 diabetes and Sjogren's syndrome are autoimmune diseases, which cause the body to attack itself. Autoimmune disorders are the third most common group of diseases in the United States and affect about 8 percent of the population, says Dr. Hsu. Sjogren's syndrome can occur alone or secondary to another autoimmune disease, such as lupus, rheumatoid arthritis or type 1 diabetes.
The study, published in the Oct. 24 issue of Life Sciences, supports earlier research showing EGCG's impact on helping prevent autoimmune disease.
Researchers treated a control group of mice with water and a test group with a purified form of EGCG dissolved in the drinking water. At 16 weeks, the EGCG-fed mice were 6.1 times more likely to be diabetes-free than the water-fed group, and 4.2 times more likely at 22 weeks.
"Previous studies used another animal model that developed type 1 diabetes only after an injected chemical killed the insulin-producing cells. That may not accurately resemble disease development in humans, because type 1 diabetes is a genetic disease," says Dr. Hsu, the study's corresponding author.
"Our study is significant because we used a mouse model with the genetic defects that cause symptoms similar to human type 1 diabetes and Sjogren's syndrome, so the immune cells attack the pancreas and salivary glands until they are no longer functional."
Another related finding was that even when salivary cells were under attack, they seemed to be rapidly reproducing in the control group. The proliferation was suppressed in the EGCG-fed group.
"It's kind of counterintuitive – why would there be proliferation of the glandular cells occurring when the present cells are not secreting saliva?" says Dr. Kevin Gillespie, first author of the study he conducted for his master's research project at MCG.
The proliferation phenomenon also can be observed in psoriasis, an autoimmune disease affecting the skin and joints, says Dr. Hsu. "Normal skin cells turn over every 30 days or so, but skin cells with psoriasis turn over every two or three days." Dr. Hsu's group previously found that green tea polyphenols, including EGCG, inhibited rapid proliferation in an animal model for human psoriasis.
"We never thought proliferation was going on to this extent in the salivary gland, but we now believe it is tightly associated with Sjogren's syndrome," he says.
The next step is to observe Sjogren's syndrome in human salivary gland samples to determine whether the study findings hold up in humans.
"If the abnormal expression of these genes is the same in humans as in the animal model, then the second stage will be intervention and treatment with a pure form of EGCG," says Dr. Hsu.
"The benefit of using green tea in preventing or slowing these autoimmune diseases is that it's natural and not known to harm the body," says Dr. Gillespie, periodontics chief resident at Fort Gordon's Tingay Dental Clinic. "EGCG doesn't have the negative side-effects that can be associated with steroids or other medications that could otherwise be prescribed."
Flavonol in tea, cocoa, etc. & exercise = memory+
A natural compound found in blueberries, tea, grapes, and cocoa enhances memory according to newly published research. This effect increased further with exercise.
The compound, epicatechin, is one of a group of chemicals known as flavonols and has been shown previously to improve cardiovascular function in people and increase blood flow in the brain. Flavonols are found in some chocolate. The findings suggest that a diet rich in flavonols may help reduce the incidence or severity of neurodegenerative disease or cognitive disorders related to aging.
Green Tea Blocks Benefits Of Cancer Drug
Contrary to popular assumptions about the health benefits of green tea, researchers at the University of Southern California (USC) have found that the widely used supplement renders a cancer drug used to treat multiple myeloma and mantle cell lymphoma completely ineffective in treating cancer.
The study, which found that a component of green tea extract (GTE) called EGCG destroys any anticancer activity of the drug Velcade in tumor-bearing mice, will be published in a future print edition of the journal, Blood. It is now available online at the journal’s pre-publication First Edition website.
“Our finding that GTE or EGCG blocked the therapeutic action of Velcade was completely unexpected,” says lead author Axel H. Schönthal, PhD, associate professor in the Department of Microbiology and Immunology at the Keck School of Medicine of USC. “Our hypothesis was that GTE or EGCG would enhance the anti-tumor effects of Velcade, and that a combination of GTE with Velcade (or EGCG with Velcade) would turn out to be a superior cancer treatment as compared to treatment with Velcade alone.”
Herbal remedies, including green tea, have become a popular remedy for cancer patients dealing with side effects of chemotherapy. However, these supplements are unregulated and, for most, their beneficial and/or detrimental effects have not been qualified through research.
Using preclinical models and tumor-bearing mice, the researchers found that the unusually effective blockage of Velcade’s therapeutic activity was based on the chemical interaction between molecules. The EGCG molecule and the Velcade molecule were able to form chemical bonds, meaning that the Velcade molecule could no longer bind to its intended target inside the tumor cells.
Clinical trials to verify these results in humans would be highly unethical to conduct, because of the predictably unfavorable outcome. Nevertheless, the researchers expect the results of the study to be applicable to cancer patients.
“The most immediate conclusion from our study is the strong advice that patients undergoing cancer therapy with Velcade must avoid green tea, and in particular all of its concentrated products that are freely available from health food stores,” says Schönthal. “It is important to spread this message to health care providers who administer Velcade to patients.”
Schönthal points out that for patients on Velcade, supplementing with green tea products should reduce the burden of harsh side effects—which might be attractive to the patient, but comes at a high cost.
“Essentially, in addition to not being able to attack tumor cells, Velcade would be unable to cause side effects either,” he says. “As a result, the patient would feel a lot better and conclude that the consumption of GTE helped cope with side effects—while in reality, Velcade simply wasn’t active in the first place.”
The research findings are part of a larger project run by the team called “Yin-Yang Properties of Green Tea Extract in Combination Cancer Chemotherapy: From Encouragingly Beneficial to Dangerously Detrimental.”
“Obviously, the combination of GTE or EGCG with Velcade is an example of ‘dangerously detrimental,’ ”Schönthal says. “But we are also studying another well-established chemotherapeutic drug, where the inclusion of EGCG appears to yield an ‘encouragingly beneficial’ outcome, which is more in line with our original expectation that GTE should be beneficial, not detrimental.”
Oatmeal etc. Protects Against Heart Failure
Eating whole-grain breakfast cereals seven or more times per week was associated with a lower risk of heart failure, according to an analysis of the observational Physicians' Health Study. Researchers presented findings of the study today at the American Heart Association's 47th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. For the present study, breakfast cereals that contain at least 25 percent oat or bran content were classified as whole grain cereals.
The analysis shows that those who ate a whole-grain breakfast cereal seven or more times per week were less likely (by 28 percent) to develop heart failure over the course of the study than those who never ate such cereal. The risk of heart failure decreased by 22 percent in those who ate a whole-grain breakfast cereal from two to six times per week and by 14 percent in those who ate a whole-grain breakfast cereal up to once per week.
According to researchers, if this data is confirmed by other studies, a healthy diet including whole-grain breakfast cereals along with other measures may help reduce the risk of heart failure.
"There are good and powerful arguments for eating a whole-grain cereal for breakfast," said Luc Djoussé, M.D., M.P.H., D.Sc., lead author of the study and assistant professor of medicine in the Division of Aging at Brigham & Women's Hospital and Harvard Medical School in Boston, Mass. "The significant health benefits of whole-grain cereal are not just for kids, but also for adults. A whole-grain, high-fiber breakfast may lower blood pressure and bad cholesterol and prevent heart attacks."
Djoussé urges the general public to consider eating a regular whole-grain, high fiber breakfast for its overall health benefits.
In the Physicians' Health Study, the majority of the physicians in the study ate whole-grain cereals rather than refined cereals. Whole grains are rich in vitamins, minerals, and anti-oxidants and have a high fiber content. Of 10,469 physicians reporting cereal consumption at baseline, 8,266 (79 percent) ate whole-grain cereals compared to 2,203 (21 percent) who ate refined cereals.
Among the physicians who ate whole-grain breakfast cereals, 2,873 (35 percent) said they ate them seven or more times per week; 3,240 (39 percent) said two to six times per week; and 2,153 (26 percent) said they ate up to one cereal serving per week.
The findings reported here were based on annual detailed questionnaires about major heart events and reported breakfast cereal consumption at baseline. However, the results did not change when possible changes in cereal consumption over time (assessed at 18 weeks; two years; four years; six years; eight years; and ten years) were taken into account. Researchers conducted the study from 1982 to 2006. The average age of physicians in the study at baseline was 53.7 years. Djoussé hopes the findings of the Physicians' Health Study will encourage the general population to eat heart-healthy diets.
"The Physicians' Health Study shows that even in a population with overall healthy behavior, it is possible to see less heart failure in those who eat a whole-grain cereal breakfast," Djoussé said.
In the United States, foods considered "whole grain" contain 51 percent or more whole grain ingredients by weight per reference amount customarily consumed.
Red wine may lower lung cancer risk
Moderate consumption of red wine may decrease the risk of lung cancer in men, according to a report in the October issue of Cancer Epidemiology, Biomarkers & Prevention¸ a journal of the American Association for Cancer Research.
"An antioxidant component in red wine may be protective of lung cancer, particularly among smokers," said Chun Chao, Ph.D., a research scientist at Kaiser Permanente Department of Research and Evaluation in Pasadena, California.
Chao analyzed data collected through the California Men's Health Study, which linked clinical data from California's health system with self-reported data from 84,170 men aged 45 to 69 years. Researchers obtained demographics and lifestyle data from surveys computed between 2000 and 2003, and identified 210 cases of lung cancer.
Researchers measured the effect of beer, red wine, white wine and liquor consumption on the risk of lung cancer. Adjustments were made for age, race/ethnicity, education, income, body mass index, history of chronic obstructive pulmonary disease or emphysema, and smoking history.
Among the study participants, there was on average a two percent lower lung cancer risk associated with each glass of red wine consumed per month. The most substantial risk reduction was among smokers who drank one to two glasses of red wine per day. The researchers reported a 60 percent reduced lung cancer risk in these men. Researchers warned men to stop smoking as the best way to reduce lung cancer risk; noting that even men who drank one to two glasses of red wine per day still face higher lung cancer risk than do non-smokers.
No clear associations with lung cancer were noted for consumption of white wine, beer, or liquor. "Red wine is known to contain high levels of antioxidants. There is a compound called resveratrol that is very rich in red wine because it is derived from the grape skin. This compound has shown significant health benefits in preclinical studies," Chao said.
Chao said their findings should not be construed to recommend heavy alcohol consumption.
Red, red wine: How it fights Alzheimer's
Researchers discover how compounds found in wine thwart disease in mice
Scientists call it the "French paradox" — a society that, despite consuming food high in cholesterol and saturated fats, has long had low death rates from heart disease. Research has suggested it is the red wine consumed with all that fatty food that may be beneficial — and not only for cardiovascular health but in warding off certain tumors and even Alzheimer's disease.
Now, Alzheimer's researchers at UCLA, in collaboration with Mt. Sinai School of Medicine in New York, have discovered how red wine may reduce the incidence of the disease. Reporting in the Nov. 21 issue of the Journal of Biological Chemistry, David Teplow, a UCLA professor of neurology, and colleagues show how naturally occurring compounds in red wine called polyphenols block the formation of proteins that build the toxic plaques thought to destroy brain cells, and further, how they reduce the toxicity of existing plaques, thus reducing cognitive deterioration.
Polyphenols comprise a chemical class with more than 8,000 members, many of which are found in high concentrations in wine, tea, nuts, berries, cocoa and various plants. Past research has suggested that such polyphenols may inhibit or prevent the buildup of toxic fibers composed primarily of two proteins — Aß40 and Aß42 — that deposit in the brain and form the plaques which have long been associated with Alzheimer's. Until now, however, no one understood the mechanics of how polyphenols worked.
Teplow's lab has been studying how amyloid beta (Aß) is involved in causing Alzheimer's. In this work, researchers monitored how Aß40 and Aß42 proteins folded up and stuck to each other to produce aggregates that killed nerve cells in mice. They then treated the proteins with a polyphenol compound extracted from grape seeds. They discovered that polyphenols carried a one-two punch: They blocked the formation of the toxic aggregates of Aß and also decreased toxicity when they were combined with Aß before it was added to brain cells.
"What we found is pretty straightforward," Teplow said. "If the Aß proteins can't assemble, toxic aggregates can't form, and thus there is no toxicity. Our work in the laboratory, and Mt. Sinai's Dr. Giulio Pasinetti's work in mice, suggest that administration of the compound to Alzheimer's patients might block the development of these toxic aggregates, prevent disease development and also ameliorate existing disease."
Human clinical trials are next.
"No disease-modifying treatments of Alzheimer's now exist, and initial clinical trials of a number of different candidate drugs have been disappointing," Teplow said. "So we believe that this is an important next step."
Vitamin D Tied to Muscle Power in Adolescent Girls
Vitamin D is significantly associated with muscle power and force in adolescent girls, according to a new study accepted for publication in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).
Although vitamin D is naturally produced in the body through exposure to direct sunlight, vitamin D deficiency has become widely common in the United States. Vitamin D deficiency has been shown to have a significant negative impact on muscle and bone health, and can lead to conditions including osteoporosis and rickets.
“We know vitamin D deficiency can weaken the muscular and skeletal systems, but until now, little was known about the relationship of vitamin D with muscle power and force,” said Dr. Kate Ward, Ph.D., of the University of Manchester in the U.K., and lead author of the study. “Our study found that vitamin D is positively related to muscle power, force, velocity and jump height in adolescent girls.”
For this study, researchers followed 99 adolescent girls between the ages of 12 and 14 years. Dr. Ward and her colleagues took blood samples to measure the girls’ serum levels of vitamin D. Many of these girls were found to have low levels of vitamin D despite not presenting any symptoms.
Researchers used a novel outcome measure called jumping mechanography to measure muscle power and force. Jumping mechanography derives power and force measurements from a subject’s performance in a series of jumping activities. Dr. Ward says this method of testing is ideal as the muscles required to jump are those most often affected in subjects with vitamin D deficiency. Girls without vitamin D deficiency performed significantly better in these tests.
“Vitamin D affects the various ways muscles work and we’ve seen from this study that there may be no visible symptoms of vitamin D deficiency,” said Dr. Ward. “Further studies are needed to address this problem and determine the necessary levels of vitamin D for a healthy muscle system.”
Other researchers working on the study include Geeta Das of the Longsight Health Centre in Manchester, U.K.; Jacqueline Berry, Stephen Roberts, and Judith Adams of the University of Manchester in the U.K.; Rainer Rawer of Novotec Medical GmBH in Pforzheim, Germany; and Zulf Mughal of Saint Mary’s Hospital for Women & Children in Manchester, U.K.
The article “Vitamin D Status and Muscle Function in Post-Menarchal Adolescent Girls,” will appear in the February 2009 issue of JCEM.
Lack of 'Sunshine vitamin' linked to cognitive problems in older people
Vitamin D linked to cognitive impairment
Researchers from the Peninsula Medical School, the University of Cambridge and the University of Michigan, have for the first time identified a relationship between Vitamin D, the "sunshine vitamin", and cognitive impairment in a large-scale study of older people. The importance of these findings lies in the connection between cognitive function and dementia: people who have impaired cognitive function are more likely to develop dementia. The paper will appear in a forthcoming issue of the Journal of Geriatric Psychology and Neurology.
The study was based on data on almost 2000 adults aged 65 and over who participated in the Health Survey for England in 2000 and whose levels of cognitive function were assessed. The study found that as levels of Vitamin D went down, levels of cognitive impairment went up. Compared to those with optimum levels of Vitamin D, those with the lowest levels were more than twice as likely to be cognitively impaired.
Vitamin D is important in maintaining bone health, in the absorption of calcium and phosphorus, and in helping our immune system. In humans, Vitamin D comes from three main sources – exposure to sunlight, foods such as oily fish, and foods that are fortified with vitamin D (such as milk, cereals, and soya drinks). One problem faced by older people is that the capacity of the skin to absorb Vitamin D from sunlight decreases as the body ages, so they are more reliant on obtaining Vitamin D from other sources.
According to the Alzheimer's Society, dementia affects 700,000 people in the UK and it is predicted that this figure will rise to over 1 million by 2025. Two-thirds of sufferers are women, and 60,000 deaths a year are attributable to the condition. It is believed that the financial cost of dementia to the UK is over £17 billion a year.
Dr. Iain Lang from the Peninsula Medical School, who worked on the study, commented: "This is the first large-scale study to identify a relationship between Vitamin D and cognitive impairment in later life. Dementia is a growing problem for health services everywhere, and people who have cognitive impairment are at higher risk of going on to develop dementia. That means identifying ways in which we can reduce levels of dementia is a key challenge for health services."
Dr Lang added: "For those of us who live in countries where there are dark winters without much sunlight, like the UK, getting enough Vitamin D can be a real problem – particularly for older people, who absorb less Vitamin D from sunlight. One way to address this might be to provide older adults with Vitamin D supplements. This has been proposed in the past as a way of improving bone health in older people, but our results suggest it might also have other benefits. We need to investigate whether vitamin D supplementation is a cost-effective and low-risk way of reducing older people's risks of developing cognitive impairment and dementia."
Vitamin D Found to Stimulate a Protein that Inhibits the Growth of Breast Cancer Cells
Calcitrol, the active form of vitamin D, has been found to induce a tumor suppressing protein that can inhibit the growth of breast cancer cells, according to a study by researcher Sylvia Chistakos, Ph.D., of the UMDNJ-New Jersey Medical School.
Chistakos, a professor of biochemistry, has published extensively on the multiple roles of vitamin D, including inhibition of the growth of malignant cells found in breast cancer. Her current findings on the vitamin D induced protein that inhibits breast cancer growth are published in a recent issue of The Journal of Biological Chemistry.
Previous research had determined that increased serum levels of vitamin D are associated with an improved diagnosis in patients with breast cancer. Prior to the current study, little was known about the factors that determine the effect of calcitrol on inhibiting breast cancer growth, she said.
During the study, Christakos and co-author Puneet Dhawan, Ph.D., examined the protein involved in the action that can reduce the growth of vitamin D in breast cancer cells. “These results provide an important process in which the active form of vitamin D may work to reduce growth of breast cancer cells,” said Christakos. “These studies provide a basis for the design of new anticancer agents that can target the protein as a candidate for breast cancer treatment.”