antioxidants

Description

Antioxidants are a broad group of compounds that destroy single oxygen molecules, also called free radicals, in the body, thereby protecting against oxidative damage to cells. They are essential to good health and are found naturally in a wide variety of foods and plants, including many fruits and vegetables. Many antioxidants, either singly or in combination, are also available as over-the-counter nutritional supplements in tablet or capsule form. The most commonly used antioxidants are vitamin C, vitamin E, and beta carotene. Others include grape seed extract, vitamin A, selenium, and coenzyme Q₁₀. It is unknown whether or not supplemental antioxidants provide the same benefits as those occurring naturally in foods, however.

General use

In brief, antioxidants destroy free radicals in the body. Free radicals are byproducts of oxygen metabolism that can damage cells and are among the causes of many degenerative diseases, especially diseases associated with aging. They are also associated with the aging process itself. As a person ages, cell damage accumulates, and supplementing the diet with extra antioxidant-rich foods can help slow the oxidative damage done to cells. Scientific studies validate the role of antioxidants in preventing many diseases. Although studies have shown lower rates of cancer and heart disease in people who eat a recommended amount of fruits and vegetables, recent clinical studies have shown that supplementation of diet with antioxidant vitamin therapy does not lower risk of cardiovascular disease or certain other diseases.

Many herbs and medicinal plants are good natural sources of antioxidants. These include carrots, tomatoes, yams, leafy greens, blueberries, billberries, ginkgo biloba, garlic, and green tea, to name a few. A diet rich in vitamin C, vitamin E, and beta carotene may help reduce the risk of some cancers, heart disease, cataracts, and strokes.

Vitamin A

A study by the University of Arizona found that vitamin A has a protective affect against many types of cancer, according to Dr. Michael Colgan in his book, The New Nutrition. Vitamin A is a fat-soluble antioxidant found in animal products but can be made by the body from its precursor, beta carotene. Foods rich in vitamin A are liver, eggs, and fortified dairy products. Vitamin A helps bones and teeth develop, and promotes vision. As an antioxidant, it protects cell membranes and fatty tissue, helps repair damage caused by air pollutants, and boosts the immune system. A deficiency of this vitamin can result in dry skin, brittle hair, vision problems, blindness, and increased susceptibility to respiratory infections.

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Author Info: Ken R. Wells, Teresa G. Odle, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Alternative Medicine, 2005

This feature is for informational purposes only and should not be used to replace the care and information received from your healthcare provider. Please consult a healthcare professional with any health concerns you may have.