Last reviewed 08/2018

Vitamins are a group of unrelated organic substances occurring in many foods in small amounts and necessary in trace amounts for the normal metabolic functioning of the body. They cannot be synthesized by body cells. Deficiencies, usually the result of globally poor nutrition, produce well-characterized clinical symptoms and signs.

Fat soluble vitamins:

  • vitamins A, D, E, K

Water soluble vitamins:

  • vitamins B1, B2, niacin, B6, B12, pantothenic acid, folic acid, biotin, C

Water soluble vitamins are less readily stored than their fat soluble counterparts. Consequently, in the absence of intake, deficiencies of the former tend to occur more rapidly.

In illness, an elevation of the metabolic rate increases the turnover of vitamins and particularly the water soluble group. This is because they are largely involved as co-factors in a number of metabolic pathways. Consequently, allowance should be made for additional supplementation in such circumstances.

The term `vitamine' came into use in 1912, when it was thought that the compound in question was an amine essential to life. The `e' was subsequently dropped when it became clear that these substances were not amines.