green tea - Helps reduce risk of osteoporosis, cancer, heart disease, and cavities. Green tea contains a rich concentration of flavonoids and polyphenols, natural antioxidants that may protect cells from carcinogens (cancer-causing substances) and inhibit tumor growth by helping to neutralize free radicals in the body. The tea's antioxidants may also guard against heart disease by relaxing blood vessels, inhibiting the formation of blood clots that trigger heart attacks and strokes. Green tea also contains fluoride, which strengthens teeth; the flavonoids may build up bones as well, reducing the risk of osteoporosis and tooth decay.