Oxidative stress from free radicals causes a variety of diseases, including cardiovascular disease, diabetes, Alzheimer's, Parkinson's, and eye problems such as cataracts and age-related macular degeneration. Antioxidants slow down these processes, and in some cases reverse them by repairing damaged cells.
The symptoms of lack of antioxidants include the following:
Frequent contagious diseases;
Hair loss, brittle nails;
The scientists have not yet reached common ground on benefits of consuming large amounts of antioxidants in the form of supplements. Overabundance of them, at best, has no effect, at worst, is harmful. The National Institutes of Health study shows that high doses of beta-carotene are associated with an increased risk of lung cancer in smokers. Excessive consumption of antioxidants can be toxic and promote oxidative damage rather than prevent it. This phenomenon is known as the antioxidant paradox.
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