ABSTRACT
Vitamins are dietary factors obtained from organic sources and are essential to life. They are required in very small amounts for normal metabolic functioning, i.e., cell maintenance and differentiation, function, and growth. They often function as coenzymes and have important metabolic roles. Other micronutrients (choline, taurine, inositol, and carnitine) play important metabolic roles in the body and may be classified as vitamins in the future as their role in metabolism is further elucidated.
