Antioxidants can either be a nutrient or an enzyme that fights free-radicals, the harmful by-products of oxidative processes occurring in the body. Free radicals have been linked to the development of several chronic diseases. Antioxidants are involved in slowing the aging process, protection from cardiovascular diseases, boosting the stamina, preventing infections, and combating the effects of smoking and other unhealthy habits. Most vitamins and minerals found in the diet have antioxidant properties. The best antioxidant foods are those rich in Vitamins A, C, E, and minerals like selenium and zinc. Other common antioxidants are Resveratrol, Grape Seed Extract, Alpha Lipoic Acid, Green Tea Extract, Pycnogenol and Astaxanthin which are also available as antioxidant supplements.