WHAT ANTIOXIDANTS CAN -- AND CAN'T -- DO
Scientists began to theorize that free-radical
damage was involved in the early stages of atherosclerosis and might
play a role in the development of many other chronic medical conditions
in the 1990s. Studies at the time suggested that people who ate few
antioxidant-rich fruits and vegetables had a greater risk of developing
these medical conditions. So began several clinical trials in which
antioxidant supplements like beta carotene and vitamin E were tested for
their protection against heart disease, cancer, and other conditions.
As a result, "antioxidants" became a buzzword in the '90s, and their
benefits were glorified by the media, by the the food industry who began
labeling foods as "rich in antioxidants," and by the supplement
industry as they began hyping the health benefits of antioxidant
supplements. They were even promoted as anti-aging ingredients in
False Hype Regarding Aging and a Risk to Prostates
However, the research results were mixed and the
anticipated benefits were not clearly present. While some trials
reported beneficial effects, especially on cognitive decline, the hope that vitamin E would protect against heart disease and cancer did not pan out as anticipated. In fact, at least one study showed that taking antioxidant supplements increased the risk of lung cancer in smokers, and most recently, vitamin E was found to increase the risk of prostate cancer. As much as we would like to think a compound in food can forestall aging, antioxidants are not likely the answer.
Despite the lack of definitive research, antioxidants are still being
promoted as food additives and supplements that can prevent a plethora
of medical conditions including heart disease, cancer, cataracts, and memory loss, and they are still advertised as active ingredients in anti-aging products.
Important for the Eyes
Perhaps the most promising area in antioxidant research is the area of eye health. A study
found that a combination of the antioxidants beta carotene, vitamins C
and E, and the mineral zinc reduced the risk of developing advanced
stages of age-related macular degeneration (AMD) in those who had intermediate or advanced AMD in one eye.
IS THERE ANY HARM IN TAKING ANTIOXIDANT SUPPLEMENTS?
Whether they are taken singularly or in combination
concoctions, antioxidants could have adverse health effects, as the
prostate cancer and lung cancer studies mentioned earlier suggest.
Supplementation has also been linked to an increased risk of skin cancer
in women. Another study indicated that those who took vitamin A, E, and
beta carotene supplements may be at risk for premature death.
Excessive intake of vitamin E has also been associated with heart
failure and increased bleeding.
The Food and Drug Administration does not regulate
dietary supplements, and they can be sold with little or no research as
to their safety, purity, and effectiveness. Dietary supplement
manufacturing methods are not always standardized,
so how well they work and their side effects can differ between brands
or even within a brand. The form of a dietary supplement purchased in a
drug store or health food store is likely not the same form used in
research. The long-term effects of supplemental antioxidants are not