Chromium is an essential trace element required for normal carbohydrate metabolism. The biological function of chromium is closely associated with that of insulin and most chromium-stimulated reactions are also insulin dependent. Proper chromium nutrition leads to a decreased requirement for insulin and also an improved blood lipid profile. Most fresh foods and minimally processed foods are good sources of dietary chromium. Inorganic chromium does not potentiate insulin action and must be converted to an organic biologically active form. An organic form of chromium capable of potentiating insulin has been isolated from brewer's yeast and was shown to contain: Cr, nicotinic acid and a combination of amino acids. Synthetic insulin potentiating organic chromium complexes containing chromium, nicotinic acid, glycine, cysteine, and glutamic acid or chromium, nicotinic acid and glutathione have been prepared. These complexes have not been purified to homogeneity since they dissociate during purification. Suitable analytical bioassays are available to measure total chromium and the organic biologically-active forms of chromium, respectively.