Vitamin E - As Good As A Vitamin Gets?

Updated: 11/9/98

Submitted by Christopher Wiechert Newsstand Resources Ask Mayo What's Hot Brought to you by Mayo Clinic June 19, 1998 If you keep up with health news, you've probably noticed that Vitamin E has been getting a lot of attention. Vitamin E, Vitamin C and beta carotene are "antioxidants" that, in theory, are believed to help fix some of the damage due to oxygen "free radicals" Ñ oxygen molecules with a missing electron. Antioxidants may donate an electron to free radicals. Without this contribution by the antioxidant, free radicals may otherwise take electrons from vital cell structures, damaging cells and possibly leading to disease. The role of antioxidants in health continues to be an area of debate. Recent studies have suggested several potential benefits of vitamin E, including: Supplemental vitamin E appears to have a protective effect against cardiovascular disease. Supplemental vitamin E has been associated with a reduced risk of some cancers. a.. Vitamin E and prostate cancer - A Mayo perspective a.. Supplemental vitamin E may slow the progression of AlzheimerÕs disease. a.. Antioxidants may slow progression of AlzheimerÕs disease b.. Can you reduce your risk of developing AlzheimerÕs? a.. A diet high in vitamin E appears to have a protective effect against ParkinsonÕs disease. b.. Taking Vitamin E pills may enhance immune function in elderly people. Mayo Clinic Health Oasis asked Donald D. Hensrud, M.D., a nutrition and preventive medicine specialist at Mayo Clinic, Rochester, Minn., for help in interpreting current evidence about vitamin E. Oasis: At first glance, the news about vitamin E looks pretty good. Does it still look good when you take an in-depth look? Dr. Hensrud: Yes, the news concerning vitamin E looks very promising. One of the things weÕre seeing is a consistently beneficial effect of vitamin E across a spectrum of diseases. Much of the evidence has been from basic science and observational, uncontrolled studies. Of course, randomized, controlled trials provide the strongest evidence. Now there are more randomized trials that show a beneficial effect. a.. Clinical trials: Difficult, imperfect, expensive - and necessary Oasis: Many studies look at other antioxidants (especially vitamin C) and supplements as well as vitamin E. Does that muddy the waters? Dr. Hensrud: Most studies try to control for the effects of different supplements so that any measurable effects can be evaluated separately. However, without doing randomized trials with head-to-head comparisons of different supplements, we can never be absolutely certain. So there are questions about exactly what is causing the good effects. But the alpha-tocopherol form of vitamin E Ñ which was used in most of this research Ñ is clearly an important contributor in many of the beneficial effects found so far. Oasis: You mention the alpha-tocopherol form of vitamin E. Does that mean that vitamin E comes in several forms? Dr. Hensrud: Yes, there are a number of tocopherols as well as other substances that have vitamin E activity. Many of those also seem to have beneficial effects. Most of the evidence of benefits from vitamin E comes from alpha-tocopherol in supplements. But at least one study showed benefits from dietary vitamin E as opposed to supplemental vitamin E. Oasis: Are there known risks in taking vitamin E? Dr. Hensrud: Vitamin E isnÕt recommended for people taking blood-thinning (anticoagulant) medications because it can complicate the proper control of blood thinning. Oasis: Doses of vitamin E given to study participants vary, ranging from 50 international units (IU) to 1,200 IU. What is the current thinking about the optimum dose of vitamin E? Dr. Hensrud: It appears that at least 100 IU per day is necessary for any beneficial effect on the heart. The dose usually recommended for heart patients is 400 IU per day, which is the amount found in most vitamin E supplements. One recent study showed that at doses of 1,000 IU, vitamin E had a pro-oxidant, rather than antioxidant, effect. ThatÕs not conclusive, but until we know more, I believe people should stay at 400 IU or lower. Oasis: Do you recommend supplemental vitamin E to patients? Dr. Hensrud: I recommend it to heart patients. For others, the benefits may outweigh the risks, although I think itÕs an individual choice. In general, I recommend getting vitamins and nutrients through the diet whenever possible. But in the case of vitamin E, itÕs difficult to get the amount believed to be beneficial through diet alone. A multivitamin and vitamin E are the two supplements I recommend most often. Oasis: In terms of prevention of disease, how important is taking vitamin E compared with abiding by the recommendations for healthful eating and exercise? Dr. Hensrud: Many people believe that antioxidants such as vitamin E have a powerful effect, comparable to maintaining a healthful diet and getting regular physical activity. Although there may be some potential benefits emerging from the study of vitamin E, such effects are MUCH, MUCH less than the potential benefits of healthful diet and activity patterns. a.. Vitamin and nutritional supplements - Sorting out fact from fiction amid a storm of controversy b.. Straight talk about anti-wrinkle products Please send E-mail to: joyful@best.com if you have any questions.