Scientific experts in pharmacology, toxicology and nutrition gathered at the University of Southern California (USC) on February 26 for a forum to discuss the benefits and safety of vitamin E.
The group concluded that due to promising results from existing clinical studies, antioxidant supplements are safe and appear to confer a health benefit in certain individuals. Future research in well-defined populations with both clinical and biomarker end-points needs to be undertaken.
During the day-long forum, scientists discussed topics ranging from the effects of vitamin E on neurological disorders and cardiovascular disease to the overall safety of vitamin E supplementation in the general population and the elderly. Lester Packer, Ph.D., adjunct professor of molecular pharmacology and toxicology at the USC School of Pharmacy and Ishwarlal Jialal, M.D., Ph.D., Robert E. Stowell Endowed Chair in Experimental Pathology and director of the Laboratory for Atherosclerosis and Metabolic Research at UC Davis School of Medicine, led this group of nine scientists in panel discussions reviewing clinical research demonstrating the value of vitamin E supplementation to human health.
Vitamin E, a fat-soluble vitamin, acts as an antioxidant to protect cells in the body against the effects of free radicals, which are potentially damaging by-products of cell metabolism. Common food sources of vitamin E include vegetable oils, nuts, green leafy vegetables, and fortified cereals.
Current U.S. Department of Agriculture (USDA) guidelines advise that a person's daily intake of vitamin E should be met primarily through food sources, but that many Americans require supplements to get the nutrients they need. Vitamin E supplement capsules typically contain 400 IU to 800 IU. The Institute of Medicine advises adults can consume up to 1500 IU of vitamin E a day.
Numerous scientific studies suggest vitamin E supplements offer a variety of health benefits including helping to reduce the risk of heart disease, cancer and Alzheimer's disease. A study conducted by Johns Hopkins University, published in the Journal of Archives of Neurology in 2004 found in 4,740 men and women over age 65 who took daily doses of 500-1500 mg of vitamin C and 400-1000 IU of Vitamin E reduced the prevalence and risk of Alzheimer disease. Vitamins C and E are associated with maintaining the health of brain cells.
In November 2004, another John Hopkins meta-analysis found that older patients (47-84 years of age) with existing conditions such as heart disease, Parkinson's disease and kidney disease, who took more than 400 IUs of vitamin E or more per day, had an increased risk of all-cause mortality. But the study noted, "overall, vitamin E supplementation did not affect all cause mortality." The study also concluded, "... high dosage vitamin E trials were often performed in patients with various chronic diseases, and we could not evaluate the generalizability of our findings to healthy adult populations."
Referencing the body of clinical research on vitamin E safety, scientists participating in the USC Vitamin E Forum agreed it would be premature to apply this study's isolated findings to the general population. The group urged the scientific community to conduct long-term, large-scale trials on vitamin E supplementation in well-defined populations because they appear to be beneficial to the health of certain individuals.