Intake recommendations for chromium and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by an expert committee of the FNB at the National Academies of Sciences, Engineering, and Medicine. However, no validated methods for determining chromium status and no clinically defined chromium deficiency state exist. Hair levels might reflect past chromium intakes, and some studies have measured chromium levels in hair, sweat, serum, and toenails. However, because these levels are closely related to recent chromium intakes, they are not good indicators of chromium body stores. Urinary chromium levels are therefore a good indicator of chromium absorption. Ĭhromium is excreted mainly in the urine. Chromium accumulates mainly in the liver, spleen, soft tissue, and bone. In the blood, most chromium is bound to plasma proteins, particularly transferrin, and only about 5% is unbound. However, in 2014, the European Food Safety Authority Panel on Dietetic Products, Nutrition and Allergies concluded that no convincing evidence shows that chromium is an essential nutrient and, therefore, setting chromium intake recommendations would be inappropriate. The FNB has not evaluated chromium since 2001. However, recent research has suggested that although chromium might have benefits at pharmacologic amounts (e.g., in the hundreds of mcg), it is not an essential mineral because an absence or deficiency of chromium does not produce abnormalities that can be reversed with the addition of chromium (see the Chromium Deficiency section below). In 2001, the Food and Nutrition Board (FNB) of the National Academies of Sciences, Engineering, and Medicine considered chromium to be an essential nutrient based on its effects on insulin action. Chromium might also have antioxidant effects. Although the precise mechanism for this activity has not been identified, scientists have proposed that chromium binds to an oligopeptide to form chromodulin, a low-molecular-weight, chromium-binding substance that binds to and activates the insulin receptor to promote insulin action. This fact sheet focuses entirely on trivalent chromium.Ĭhromium might play a role in carbohydrate, lipid, and protein metabolism by potentiating insulin action.
Chromium also exists as hexavalent (+6) chromium, a toxic by-product of stainless steel and other manufacturing processes.
IntroductionĬhromium, as trivalent (+3) chromium, is a trace element that is naturally present in many foods and available as a dietary supplement. For a general overview of Chromium, see our consumer fact sheet on Chromium. This is a fact sheet intended for health professionals.
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