Claims, Benefits: Builds muscle, prevents and treats diabetes,
promotes weight loss.
Bottom Line: Chromium is an essential mineral, but deficiency is rare
in the U.S. There's no evidence that chromium supplements perform
as claimed, promote weight loss, or benefit healthy people. There is
some evidence that the picolinate form may harm cells. Diabetics
should take only on medical advice.
Chromium 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. This fact sheet focuses exclusively
on trivalent (3+) chromium.
Chromium is known to enhance the action of insulin [1-3], a hormone
critical to the metabolism and storage of carbohydrate, fat, and
protein in the body [4]. In 1957, a compound in brewers' yeast was
found to prevent an age-related decline in the ability of rats to
maintain normal levels of sugar (glucose) in their blood [3].
Chromium was identified as the active ingredient in this so-called
"glucose tolerance factor" in 1959 [5].
Chromium also appears to be directly involved in carbohydrate, fat,
and protein metabolism [1-2,6-11], but more research is needed to
determine the full range of its roles in the body. The challenges to
meeting this goal include:
Defining the types of individuals who respond to chromium
supplementation;
Evaluating the chromium content of foods and its bioavailability;
Determining if a clinically relevant chromium-deficiency state exists in
humans due to inadequate dietary intakes; and
Developing valid and reliable measures of chromium status [9].
Is chromium safe?
The chromium found in foods will not hurt you. However, taking excessive chromium supplements can lead to stomach problems
and low blood sugar (hypoglycemia). Too much chromium from supplements can also damage the liver, kidneys, and nerves,
and it may cause irregular heart rhythm. However, side effects from taking chromium supplements are rare.
Antacids (including calcium carbonate) interfere with the absorption of chromium.
Being exposed to chromium on the job (such as in metallurgy and electroplating) has been linked to kidney damage and lung
cancer, as well as skin conditions such as eczema and other inflammations of the skin.
