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Supplements for men and women over 50 may improve diet deficiency
Men and women over the age of 51 who regularly take dietary supplements are more likely to get adequate amounts of several vitamins and minerals than those who do not, a new study in the Journal of the American Dietetic Association states.
Researchers also found that a substantial portion of people in this age range do not get enough vitamins and minerals from their diet alone and the use of supplements is necessary.
The study, comprising of 4,384 adults, (1,777 daily supplement users, 428 infrequent users and 2,179 nonusers.) found that fewer than half took supplements daily. Those who did met recommended levels for vitamins A, B and C as well as iron, folate, and zinc,
Researcher Rhonda Sebastian from the US Department of Agriculture said: "These widespread inadequacies should be considered when developing recommendations for supplement use for clients in this age group."
Sebastian and her team found that from diet alone a significantly smaller proportion of supplement users than nonusers had intakes below the estimated average requirement (EAR) for vitamins A, B-6, and C; folate; zinc; and magnesium. Less than half of both users and nonusers met the EAR for folate, vitamin E, and magnesium from food sources alone.
Supplements improved the nutrient intake of older adults, with more than 80 per cent of users meeting the EAR for vitamins A, B6, B12, C, and E, folate, iron, and zinc, but not magnesium, the researchers found.
However, some supplement users, particularly men, exceeded tolerable upper intake levels for iron and zinc and a small percentage of women exceeded the upper intake level for vitamin A, they added.
Overall, supplements improved the nutrient intake of older adults and they concluded that a large "proportion of older adults do not consume sufficient amounts of many nutrients from foods alone. Supplements compensate to some extent, but only an estimated half of this population uses them daily.
"Modifying dietary attitudes may result in a higher rate of supplement use in this at-risk population."
Source: Journal of the American Dietetic Association
Older Adults Who Use Vitamin/Mineral Supplements Differ from Nonusers in Nutrient Intake Adequacy and Dietary Attitudes
doi:10.1016/j.jada.2007.05.010
Authors: Rhonda Sebastian, Linda Cleveland, Joseph Goldman, Alanna Moshfegh.
www.nutraingredients.com 9/18/2007
Scientists now believe that free radicals are causal factors in nearly every known disease.
By controlling free radicals; antioxidants can influence how fast and how well we age. More than 70% of Americans will die prematurely from diseases caused by or compounded by deficiencies of antioxidants. It is virtually impossible to get the optimal amount of antioxidants through food alone.
Dr. Lester Packard, University of California Berkeley
Regarded as the world's foremost antioxidant research scientist
The Natural Products Association, along with others in the science community disputed the conclusions of a new meta-analysis appearing in the February 28 edition of the Journal of the American Medical Association (JAMA) suggesting that the use of antioxidants might increase mortality risk, saying that the study was scientifically misleading and that most clinical research continues to show that antioxidants are safe and beneficial.
"Despite the authors' contention, this analysis is assessing mortality of at-risk and diseased populations - versus a healthy population - in prevention trials. The risk of mortality must be attributed to the appropriate population studied, those with an existing health condition, which it isn't in this case. Instead, those findings are generalized to a healthy general population, which is wrong on many levels," said Daniel Fabricant, Ph.D., vice president of scientific affairs for the Natural Products Association. "But what's most troubling is that people who are safely and beneficially taking vitamins might stop, which may actually put their health at greater risk."
Fabricant also expressed concern that most consumers, who are daily confronted with seemingly contradictory research findings, may understandably become confused and skeptical about such information.
"Just yesterday, for instance, a group of Swedish researchers concluded that vitamin A may help reduce some risks of stomach cancer," said Fabricant. "And ironically, this same medical journal has released a stream of studies suggesting the health benefits of antioxidants; from reduced risk of Alzheimer's disease and macular degeneration, to helping improve immune functioning in patients with HIV spectrum disease."
Other points to be considered in the context of this analysis follow:
- If a true mortality risk was to have become apparent in any of these clinical studies using antioxidants, the study would have been halted. None were. Using these same studies to now draw different conclusions is an indictment of those researchers who conducted the original study and never observed the same outcome or halted the trial.
- Nearly 160 million people in North America and Europe use the attributed supplements. If antioxidants were a significant public health risk, as the authors speculate, it would have become clearly apparent by now. This is obviously not the case: the negative effect they refer to has not been seen in the population.
- The initial hurdle for performing a clinically meaningful meta-analysis is the criteria for how similar the studies must be in order to be included in the meta-analysis. The more similar the studies, the more valid the meta-analysis. In this instance the studies are very divergent and the conclusion of the meta-analysis is not consistent with the findings of the actual clinical studies. In addition, large controlled clinical studies on antioxidants exist and the data from those studies will be much more meaningful and relevant than a piecemeal meta-analysis like this.
This new analysis has drawn criticism from both inside and outside the dietary supplements industry concerning the methodology applied, and the conclusions drawn.
The most prevalent criticism of the study has come from the diverse nature of the studies pooled together, described by one industry expert as comparing "apples and oranges".
Moreover, Meir Stampfer, a professor of nutrition and epidemiology at the Harvard School of Public Health who was not connected to the meta-analysis, told the Associated Press that the studies reviewed were too different to be able to pool them together.
"This study does not advance our understanding, and could easily lead to misinterpretation of the data," Stampfer told the AP.
"Most trials investigated the effects of supplements administered at higher doses than those commonly found in a balanced diet, and some of the trials used doses well above the recommended daily allowances and even above the tolerable upper intake level," said the reviewers.
Many of the studies included only subjects already classified as suffering from certain diseases. Indeed, only two of the studies classified as "low bias" were carried out in the 'general population'.
When taken in their entirety, antioxidants were found to have no significant effect on mortality. This result did not hold however when the reviewers looked at the nutrients singly and removed studies that they classed as having a 'high bias' in favour of the antioxidants.
Moreover, Andrew Shao, Ph.D., CRN's vice president, scientific and regulatory affairs said that the combined studies were far too diverse and different in terms of dosage, duration, study population and nutrients tested that the results of the analysis were "compromised".
Additionally, Dr. Shao noted that most of the trials included in the meta-analysis tested for secondary prevention, looking at how a nutrient works in diseased populations, instead of primary prevention studies in healthy populations.
"Combining secondary prevention and primary prevention trials and then making conclusions for the entire population is an unsound scientific approach," said Shao. "Additionally, many of the trials had limitations, including the expectation that a simple antioxidant vitamin could be expected to overturn serious illness, such as cancer or heart disease. These trials likely statistically skewed the results."
Daniel Fabricant, vice president of scientific affairs for Natural Products Association (NPA), another US-based trade association, supported this view.
"Despite the authors' contention, this analysis is assessing mortality of at-risk and diseased populations - versus a healthy population - in prevention trials. The risk of mortality must be attributed to the appropriate population studied, those with an existing health condition, which it isn't in this case. Instead, those findings are generalized to a healthy general population, which is wrong on many levels," said Fabricant.
"But what's most troubling is that people who are safely and beneficially taking vitamins might stop, which may actually put their health at greater risk."
Fabricant also stated that if a true mortality risk had been apparent in any of these clinical studies using antioxidants, the study would have been halted, but none were.
"Nearly 160 million people in North America and Europe use the attributed supplements. If antioxidants were a significant public health risk, as the authors speculate, it would have become clearly apparent by now," he said. "This is obviously not the case: the negative effect they refer to has not been seen in the population."
Source: Journal of the American Medical Association
February 28 2007, Volume 297, Pages 842-857
"Mortality in Randomized Trials of Antioxidant Supplements for Primary and Secondary Prevention: Systematic Review and Meta-analysis"
Authors: G. Bjelakovic; D. Nikolova; L. Lotte Gluud; R.G. Simonetti; C. Gluud
The Antioxidant Miracle, Lester Packard, Ph.D
www.healthy.net
Antioxidants slow age-related impairments in dogs
A University of Toronto study involving beagles indicates that cognitive stimulation may boost the effects of a diet rich in antioxidants in combating the loss of learning ability with advanced aging.
The effectiveness of two interventions, dietary fortification with antioxidants and a program of behavioral enrichment, was assessed in a longitudinal study of cognitive aging in beagle dogs. The results of this study of four groups of beagles, over a two-year period, are published in the January 2005 issue of Neurobiology of Aging.
In October 2003, a separate study conducted at the University of Toronto showed that old dogs that were on diet fortified with antioxidants such as vitamin E, vitamin C, and beta-carotene performed better on a variety of cognitive tests than dogs that were not on the diet.
"Although we found that not all cognitive functions respond to antioxidant treatment, our data suggests that antioxidants play an important role in preventing or slowing age-related cognitive impairments," said Dr Dwight Tapp.
In the latest study, one group of elderly dogs was fed a regular diet combined with regular experience. The second group received a regular diet and enriched experience; the third group an enriched diet and regular experience; and the fourth group both an enriched diet and an enriched experience.
The results suggest that behavioral enrichment or dietary fortification with antioxidants over a long-duration can slow age-dependent cognitive decline, and that the two treatments together are more effective than either alone in older dogs.
"We were really surprised just how clear-cut the benefit is of using a combined therapy," said lead investigator and psychology professor Bill Milgram.
"Since humans and dogs have many biological and behavioral parallels, I predict similar results would be attained in people," he added.
Like humans, dogs lose some of their ability to learn new information as they get older and suffer from both long-and short-term memory lapses.
January 2005,(77-90) Neurobiology of Aging
N. W. Milgram, E. Head, S. C. Zicker, C. J. Ikeda-Douglas, H. Murphey, B. Muggenburg, C. Siwak, D. Tapp and C. W. Cotman
www.nutraingredients.com
New Obesity Study Supports Antioxidant Power
New findings from Japanese researchers could help society understand the mechanistic role of obesity in the metabolic syndrome and could eventually help stem the obesity epidemic.
Metabolic syndrome is a condition marked by a combination of abdominal obesity, high blood pressure, poor blood sugar control, low HDL 'good' cholesterol and high blood fats. The constellation of health conditions increases the risk of developing Type 2 diabetes and heart disease.
Classed as an epidemic by the UN-backed World Health Organization, at least 171 million people worldwide suffer from diabetes, a figure likely to more than double to 366 million by 2030.
IIichiro Shimomura and colleagues from Osaka University, Japan, claim that fat cells of obese mice produce increased levels of toxic oxygen molecules known as reactive oxygen species (ROS) as well as the enzyme NADPH oxidase.
The scientists found that treatment of these mice with apocynin – an antioxidant that inhibits NADPH oxidase – reduced ROS production in fat cells, restored adipocytokine production to normal, improved diabetes, and reduced the levels of fat present in the blood and liver.
Although it is too early to suggest that taking antioxidants may counter the development of obesity-associated metabolic syndrome, ‘the steps leading to excess ROS generation may represent a potentially useful therapeutic target,’ say the researchers, who reported their findings in the 15 December issue of the Journal of Clinical Investigation.
The role of antioxidants in preventing health conditions is widely documented, and gaining pace with each new study published.
Linked in some research to reduced risk for cancers, especially prostate cancer, the health-boosting carotenoid antioxidant lycopene has attracted significant attention in recent years. A recent report on the $348.5 million (€291.4m) carotenoid market set to grow to €349.3 million in 2010 from market analysts Frost & Sullivan revealed that the European food and health industry, has ‘under-utilised’ the nutraceutical properties of carotenoids, and consumers are still unaware of their health benefits.
Frost & Sullivan claims that carotenoids are still used primarily as a colouring agent for the food and feed industries. Consumers in most European regions are unaware of their use as a food fortifier and this poor level of public awareness about the health benefits of carotenoids is expected to stifle market growth in the short term.
Nutraingredients.com
16/12/2004
Antioxidant Supplements Decease Risk of Heart Disease: Epidemiologic Studies Not Trumped by Clinical Trials
WASHINGTON, D.C., August 4, 2004-Epidemiologic studies, including results from at least four large cohorts, indicate that among the healthy population the long-term use of antioxidant supplements, specifically vitamin E and vitamin C, helps protect against heart disease. "It is puzzling how the American Heart Association's nutrition committee could recommend against the use of antioxidant supplements for primary prevention of heart disease, in the face of evidence such as this," said Annette Dickinson, Ph.D., president of the Council for Responsible Nutrition. "Even if recent secondary intervention trials have been disappointing, those results do not trump the epidemiological data on primary prevention." (Primary prevention is avoiding or delaying heart disease in healthy people; secondary prevention is avoiding a second heart attack or stroke in people who have already had one.)
A study of more than 80,000 nurses found that women who took vitamin E supplements for more than two years had a 41% reduction in risk of major coronary disease. (Stampfer 1993) A later study of the nurses' cohort found that women who took vitamin C supplements had a 27% reduction in risk of coronary heart disease. (Osganian 2003) A study of almost 40,000 male health professionals (mostly dentists) found that men who took vitamin E supplements for at least two years had a 37% reduction in risk of coronary disease. (Rimm 1993) A study in more than 11,000 elderly people found that those who used vitamin E supplements had a 47% reduced risk of coronary disease mortality, and those who used supplements of both vitamin E and vitamin C had a 53% reduced risk of coronary mortality. (Losonczy 1996) These are large and important effects. The exception is a study of almost 35,000 post-menopausal women that found a protective effect of vitamin E from conventional foods, but not from supplements ñ but the authors noted that relatively few of the women used vitamin E and they had no information on the duration of use. (Kushi 1996)
The American Heart Association's science advisory recognizes that the epidemiological data is compelling, but implies that such evidence applies only to the intake of antioxidants from conventional foods, and not from supplements. (AHA 2004) This is not the case, since the studies cited above specifically examined supplemental intake, and four of the five reported significant benefits in the primary prevention of heart disease associated with the use of antioxidant supplements in healthy populations.
What is the best advice for consumers? For overall health maintenance as well as potential protection against some chronic diseases, the Council for Responsible Nutrition recommends consuming the best possible diet, with lots of fruits and vegetables and two servings of fish per week; getting regular exercise; and supplementing those healthy habits with what UCLA's David Heber, M.D., has called the "basic four" nutritional supplements: a multivitamin, extra calcium, extra vitamin E, and extra vitamin C. (Heber 2001)
REFERENCES
AHA Science Advisory: Antioxidant vitamin supplements and cardiovascular disease. Circulation 2004; 110:637-641.
Heber D. What Color is Your Diet? Regan Books (HarperCollins Publishers), New York, NY, 2001.
Kushi L, et al. Dietary antioxidant vitamins and death from coronary heart disease in postmenopausal women. NEJM 1996; 334:1156-1162.
Losonczy KG, et al. Vitamin E and vitamin C supplement use and risk of all-cause and coronary heart disease mortality in older persons: the established populations for epidemiologic studies of the elderly. Am J Clin Nutr 1996; 64:190-196.
Osganian S, et al. Vitamin C and risk of coronary heart disease in women. J Am Coll Cardiology 2003; 42:246-252.
Rimm EB, et al. Vitamin E consumption and the risk of coronary heart disease in men. NEJM 1993; 328:1450-1456.
Stampfer MJ, et al. Vitamin E consumption and the risk of coronary disease in women. NEJM 1993; 328:1444-1449.
www.crnusa.org
Antioxidant Combo Speeds Up Wound Healing
A dietary supplement containing vitamin C and plant extracts helped speed up wound healing in a new study on plastic surgery patients.
The researchers from the University of Texas found that patients taking the supplement recovered from a plastic surgery procedure like a facelift three days faster than those taking placebo.
The results could be a result of the antioxidant activity present in all four ingredients in the supplement although the scientists could not tell which ingredient or combination is the active ingredient.
"We were completely surprised that this combination of supplements actually reduced the recovery time for our patients," said Rod Rohrich, president of the American Society of Plastic Surgeons and co-author of the study.
Rohrich and colleagues found patients healed 17 per cent faster by taking the mixture of bromelain, vitamin C, rutin and grape seed extract.
"Previously, it would generally take 18 days for a patient to recover from a plastic surgery procedure, such as a facelift," said co-author James Chao. "By taking these supplements right after the procedure, patients can fully heal in just 15 days.
"The supplement could bring cost savings by cutting down on healing time as well as medicine for increasing numbers of plastic surgery patients. The results also demonstrate the potential benefits of the supplement ingredients for other types of wounds.
In the study, published in the July issue of Plastic and Reconstructive Surgery (114, issue 1, 237-244), 26 healthy volunteers took part in a randomized, crossover, placebo-controlled, clinical trial consisting of two phases, each lasting 21 days. In the first phase, subjects were subjected to a 3-mm forearm skin biopsy and randomly received a placebo or oral supplement (four capsules per day for seven days).
After a two-week washout period, a second biopsy was performed to start the second phase, with each subject receiving the respective placebo or supplement capsules. Digital photographs were taken during wound healing in both phases and analyzed for wound areas and perimeters.
More than 80 per cent of the participants benefited from taking the supplements during the early phase of the healing process, which accelerated the soft-tissue wound healing compared with subjects who received the placebo.
The researchers said they observed decreased redness in the wound for subjects receiving the supplement, indicating that the supplement cocktail more than likely changed the inflammatory process. As with all wounds, if the wound stays inflamed longer, it takes longer to heal.
All of the ingredients included in the mixture, (made by Enzymes Inc, based in Parkville, Missouri) are antioxidants, which enhance cellular stability and decrease swelling. Bromelain is an anti-inflammatory agent that helps heal minor injuries, including sprains, strains and muscle injuries, and has been found to dramatically reduce postoperative swelling.
Preliminary studies also suggest that vitamin C supplements in non-deficient people can speed healing of various types of wounds and trauma, including surgery, minor injuries, herniated intervertebral disks and skin ulcers.
In addition there is evidence that both rutin and grape seed extract helps the vitamin C's activity in cells. A study at Ohio State University in 2002 found grape seed extract to help skin wounds heal faster and with less scarring, by helping regenerate damaged blood vessels and increasing the amount of free radicals in the wound site.
However Dr Rohrich warned: "This study is a bridge towards discovering if any of these individual supplements have merit separately or combined together. Only through further study can we discover how these antioxidants work to shorten recovery time for patients."
13/07/2004
NutraIngredients.com
New Data Finds Antioxidant Combo Decreases Smokers' Cancer Risk
Smokers taking a wide range of antioxidants through their diet appear to have a lower risk of lung cancer, according to a recent study.
The results counter the findings of a trial carried out in the 90s, the Finnish ATBC study, which found an increased risk of the disease for smokers with high beta-carotene intake.
In the new study, researchers from Yale University and other US institutes together with colleagues from the National Public Health Institute in Helsinki, Finland analyzed the same data but looked at the total intake of antioxidants, including selenium, vitamin E, vitamin C as well as carotenoids and flavonoids, rather than one single antioxidant.
At baseline (1985-1988), 27,111 Finnish male smokers aged 50-69 years completed a dietary questionnaire that assessed usual frequency of consumption and portion sizes for the previous 12 months. A total of 1,787 incident cases of lung cancer were identified during a follow-up period of up to 14.4 years (1985-1999).
Writing in the 1 July issue of the American Journal of Epidemiology (160:68-76), the researchers report that smokers in the top quintile of dietary antioxidant intake had a 16 per cent lower risk of lung cancer compared to those with the lowest intake.
Smokers who ate large amounts of meat had a 25 per cent decrease, despite red meat having a high oxidative effect.
The Vitality Council, a Danish organization set up by the Danish Society for Orthomolecular Medicine and producers and distributors of vitamins and minerals to inform consumers and health professionals about new research, said the results are of "great importance, because they are sourced from the same ATBC study, which has been one of the most outspoken arguments to warn against antioxidants".
It noted that two other larger studies have found the risk of lung cancer decreased up to as much as 32 per cent and 68 per cent.
The researchers add in a commentary that the original ATBC study results have been due to the fact that the smokers did not get a combination of vitamins but were given beta-carotene alone. They recommend smokers take a variety of antioxidants as a protection against cancer.
NutraIngredients.com
09/08/2004
Antioxidant Supplements May Reduce Risk of Cardiovascular Diseases in Diabetic Patients
BACKGROUND
Diabetic patients are two to four times more likely to die from cardiovascular diseases compared with people who do not have diabetes. This increased risk cannot be explained by conventional risk factors, such as elevated cholesterol levels. Considerable evidence indicates that free-radical-induced "oxidative stress" contributes to the higher risk of cardiovascular disease, and studies suggest that antioxidant supplementation may be helpful.
RESEARCH
In this review article, researchers described the relationship between oxidative stress and cardiovascular disease in diabetes. For example, people with diabetes tend to have lower blood levels of antioxidants compared with nondiabetics. The resulting oxidative stress leads to alterations in low-density lipoprotein (LDL) cholesterol, blood coagulation, and blood vessel function, each contributing to an increased risk of cardiovascular disease.
RESULTS
Clinical studies have found that supplements of several individual antioxidants--vitamin E, alpha-lipoic acid, and vitamin C--can reduce the risk of complications and death from diabetes. For example, one study of patients with end stage renal disease (42 percent of the subjects were diabetic) found that natural vitamin E supplements (800 IU daily) lowered the risk of major cardiovascular events, including heart attack and stroke, by 54 percent. Similarly, supplemental alpha-lipoic acid (600 mg daily) significantly improved nerve function in diabetic patients with neuropathy. Still other studies have found that vitamin C supplementation (500 mg daily) reduced blood pressure in nondiabetic patients with hypertension.
IMPLICATIONS
The researchers concluded, "Compelling evidence points to the role of oxidative stress in diabetic vasculopathies.However, further research is still needed to better understand the mechanisms by which different antioxidants may aid in the prevention of vascular dysfunction in diabetic patients.
"Vega-Lopez S, Devaraj S, Jialal I. Oxidative stress and antioxidant supplementation in the management of diabetic cardiovascular disease. Journal of Investigative Medicine, 2004;52:24-32.
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