ABSTRACT
Vitamins are low-molecular-weight organic compounds (or related set of compounds) that make possible several biochemical processes essential for life. They are essential substances, as they cannot be synthesized in sufcient quantities by an organism, and must be obtained from the diet. The intake of vitamins comes from foods of animal and plant origin; fruits and vegetables, in particular, are rich in them or other metabolites (provitamins) subsequently converted into active vitamins by the human organism. All the compounds structurally related to a vitamin that full the same specic function, also if less biologically active than the vitamins, are known as vitamers.
