In the early 20th century the discovery of began. Today there is a chance that there are some that are still undiscovered. The definition of vitamin is: one of several substances necessary for animal nutrition, and occurring in minute quantities in natural foods; numerous types have been distinguished, and designated by the letters of the alphabet. Each and every living animal needs vitamins to grow and be healthy. Since the human body can t produce vitamins naturally or normally produce the amounts needed, food provides the body ....