Chromium (Cr) is a mineral that humans require in trace amounts, although its mechanisms of action in the body and the amounts needed for optimal health are not well defined. It is found primarily in two forms: 1. trivalent (chromium 3+), which is biologically active and found in food, and 2. hexavalent (chromium 6+), a toxic form that results from industrial pollution. In association with insulin, Cr promotes the utilization of glucose. It is a component of a protein namely chromodulin which facilitates the binding of insulin to cell receptor sites. It is involved in lipoprotein metabolism by reducing low density lipoproteins (LDL) and increasing the high density lipoproteins (HDL). It is believed that Cr participates in the transport of amino acids into the cells of heart and liver.