2) In the early 20th century the discovery of vitamins began. Today there is a chance that there are some vitamins 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 …showed first 75 words of 705 total…

…showed last 75 words of 705 total…of Science/National Research Council in the United States establishes these RDA s. For different worldwide population groups two agencies of the United Nation, the Food and Agriculture Organization and the World Health Organization have developed RDA s. It is wise to follow the RDA. Without correct interpretation of the RDA, a person could take too many or take too few vitamins. This proves that vitamins can be beneficial of harmful depending on the usage.