The Theory of Antioxidants and Anti-AgingFound naturally in many fruits, vegetables, and other foods, antioxidants help knock out free radicals (chemical byproducts known to damage cells). When free radicals overwhelm cells, the cells are unable to recover from free-radical-induced damage. Known as oxidative stress, this process is thought to promote aging. By combating free radicals, antioxidants are thought to fight oxidative stress (and, in turn, produce an anti-aging effect).
The Science Behind Antioxidants and AgingLaboratory experiments on cells have shown that antioxidants may help counter oxidative stress and offer anti-aging benefits. In addition, data from population studies indicate that people with a higher intake of antioxidant-rich vegetables and fruits may have a lower risk of some chronic diseases linked to aging. However, few clinical trials to date have tested the anti-aging effects of antioxidants.
Despite the overall lack of human-based research on antioxidants and anti-aging, there's some evidence that antioxidants may help guard against age-related macular degeneration (one of the leading causes of blindness in the United States). In a clinical trial published in 2001, researchers followed 3,640 participants with age-related macular degeneration for an average of 6.3 years. Results showed that those who took a combination of antioxidants and zinc in supplement form had a 25 percent reduced risk of developing advanced stages of age-related macular degeneration (compared to those assigned to a placebo).