Vitamin supplements will complement your regular diet if you are not getting enough nutrients. Greater nutrition through use of vitamin supplements will support your body’s natural ability and enable your body to have optimal growth, digestion and nerve functions. Vitamins are a group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either the vitamins themselves are coenzymes, or they form integral parts of coenzymes. A substance that functions as a vitamin for one species does not necessarily function as a vitamin for another species. The vitamins differ in structure, and there is no chemical grouping common to them all.