Vitamin E describes eight related nutrient compounds found in your food or obtained from vitamin supplements. These compounds belong to a class of substances called antioxidants. Like other antioxidants, vitamin E doesn't clean out your system; instead it helps protect your body from the effects of damaging molecules called free radicals.
Vitamin E Basics
The eight forms of vitamin E are alpha-, beta-, gamma- and delta-tocotrienol, and alpha-, beta, gamma- and delta-tocopherol, the Office of Dietary Supplements explains. Of these, only alpha-tocopherol has demonstrated activity in human beings. Dietary sources of the vitamin, which most commonly contain gamma-tocopherol, include wheat germ, sunflower seeds, liver, leafy greens and cold-pressed vegetable oils. You can also purchase synthetic vitamin E supplements, which can contain either alpha-tocopherol or a mixture of tocopherol products.
Free Radicals
Free radicals damage your system by reacting in the presence of oxygen, damaging your cellular DNA or triggering cell death. Potential long-term consequences of free radical reactions in your system include the development of heart disease or cancer. Your body naturally produces some free radicals when it processes the foods in your diet for energy. Additional free radicals form in your system when you're exposed to ultraviolet radiation or environmental toxins, such as air pollution or cigarette smoke.
Vitamin E Effects
Every cell membrane in your body contains some amount of fat susceptible to free radical damage. Vitamin E is a fat-soluble vitamin, which means your body stores it in your fat and uses it as needed. When free radicals attack your cell membranes, your stored vitamin E interacts with these molecules, chemically alters their form and renders them harmless. In addition to protecting your fat, the antioxidant effects of vitamin E help protect your body's supplies of vitamins A and C. Vitamin E also helps protect your red blood cells.
Considerations
Because of its basic antioxidant effects, vitamin E has been proposed as a remedy for a variety of serious ailments, including cancer, heart disease, Alzheimer's disease, diabetes and various eye diseases. While some medically reviewed studies support these uses, the Harvard School of Public Health and the University of Maryland Medical Center note that many other equally well-reviewed studies do not support these uses. Researchers at Harvard believe that supplemental doses of vitamin E and other antioxidants may act on your body in a different way than antioxidant substances derived from food. This may explain the lack of clear effectiveness in supplement products.
References
- National Institutes of Health Office of Dietary Supplements: Dietary Supplement Fact Sheet Vitamin E
- Oregon State University Linus Pauling Institute: Vitamin E; November 2004
- University of Maryland Medical Center: Vitamin E
- Harvard School of Public Health: Antioxidants; Beyond the Hype
- Colorado State University Extension: Fat-Soluble Vitamins; J. Anderson, L. Young; August 2008
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