The discovery of vitamins gave birth to the field of nutrition. The term vitamin came to describe a group of essential micronutrients that generally satisfy the following criteria: (1) organic compounds (or class of compounds) distinct from fats, carbohydrates, and proteins; (2) natural components of foods, usually present in minute amounts; (3) not synthesized by the body in amounts adequate to meet normal physiologic needs; (4) essential in minute amounts for normal physiologic function (i.e., maintenance, growth, development, and reproduction); and (5) cause a specific deficiency syndrome by their absence or insufficiency.