Definition and purpose
Vitamins are compounds that are essential in small amounts for proper body function and growth. Vitamins are either fat soluble: A, D, E, and K; or water soluble: vitamin B and C. The B vitamins include vitamins B1(thiamine), B2 (riboflavin), and B6 (pyridoxine), pantothenic acid, niacin, biotin, folic acid (folate), and vitamin B12 (cobalamin). Vitamins also may be referred to asmicronutrients. Antioxidant vitamins are believed to protect the body from harmful free radicals that can contribute to diseases such as cancer. Antioxidant vitamins include vitamin A, C, and E. However,doses too high may increase oxidative stress and therefore may increase cancer risk.