Antioxidants

The last few years have witnessed an explosion of information on the role of oxidative stress in causing a number of serious diseases, and there appears to be a potential therapeutic role for antioxidants in preventing such diseases. For example, recent epidemiological studies have shown that a higher consumption of vitamin E and to a lesser extent β-carotene is associated with a large decrease in the rate of coronary arterial disease. The most effective dose of vitamin E is apparently 400–800 mg/day. Other studies have shown that a diet rich in fruits and vegetables leads to a marked decline in the cancer rate in most organs with the exception of blood, breast and prostate. Antioxidants play a major role in this. It is now abundantly clear that toxic free radicals play an important role in carcinogenesis. In several studies high cancer rates were associated with low blood levels of antioxidants particularly vitamin E. Similarly, vitamin C is thought to protect against stomach cancer by scavenging carcinogenic nitrosamines in the stomach.

Studies have suggested that the antioxidants occurring naturally in fresh fruits and vegetables are very beneficial and protect against excessive oxidative stress. There is still some question as to whether antioxidants in the form of dietary supplements are equally beneficial. Some scientists believe that regular consumption of such supplements interferes with the body's own production of antioxidants.