What are Vitamins
Vitamins are generally synthesized by plants and found in animals as a result of food intake and also because of synthesis of some of the vitamins by gut microorganisms. All living beings not necessarily need the same number or kind of vitamins as some of these may be produced by the organism concerned. For instance, rat can synthesize vitanii~~ C but a guinea pig or man cannot. We, human beings, in fact can synthesize only two vitamins - vitamin D and niacin.