Free radicals and antioxidant therapy have attracted a great deal of attention in recent years. Antioxidants are compounds that destroy the free radicals in the body, thereby preventing harmful oxidation-reduction reactions. Antioxidants are critical for maintaining optimum health and well-being. The best sources of antioxidants are fruits and vegetables, which provide a variety of antioxidants such as Vitamins A, C, E, and carotenoids. Currently available data are compatible with the notion that these vitamins act as chemopreventives against some important cancers, e.g., carotenoids for lung cancer, ascorbic acid for salivary gland cancer, tocopherols for head and neck cancers, etc. Thus, a greater consumption of fruits and vegetables shou...