Chromium is a mineral the body needs in very small amounts, but it plays a significant role in human nutrition. Chromium's most important function in the body is to help regulate the amount of glucose (sugar) in the blood. Insulin plays a starring role in this fundamental biological process, by regulating the movement of glucose out of the blood and into cells. Scientists believe that insulin uses chromium as an assistant (technically, a cofactor) to "unlock the door" to the cell membrane, thus allowing glucose to enter the cell. In the past, it was believed that to accomplish this the body first converted chromium into a large chemical called glucose tolerance factor (GTF). Intact GTF was thought to be present in certain foods, such as Brewer’s yeast, and for that reason such products were described as superior sources of chromium. However, subsequent investigation indicated that researchers were actually creating GTF inadvertently during the process of chemical analysis. Scientists now believe that there is no such thing as GTF. Rather, chromium appears to act in concert with a very small protein called low molecular weight chromium-binding substance (LMWCr) to assist insulin's action. LMWCr does not permanently bind chromium and is not a likely source of chromium in foods.83-85

Based on chromium's close relationship with insulin, this trace mineral has been studied as a treatment for diabetes. The results have been somewhat positive: it seems fairly likely that chromium supplements can improve blood sugar control in people with diabetes. Chromium also might be helpful for milder abnormalities in blood sugar metabolism. One study suggests that chromium might aid in weight loss, as well, but other studies failed to find this effect.

Requirments

The official US recommendations for daily intake are as follows:

  • Infants
    • 0-6 months: 0.2 mcg
    • 7-12 months: 5.5 mcg
  • Children
    • 1-3 years: 11 mcg
    • 4-8 years: 15 mcg
  • Males
    • 9-13 years: 25 mcg
    • 14-50 years: 35 mcg
    • 50 years and older: 30 mcg
  • Females
    • 9-13 years: 21 mcg
    • 14-18 years: 24 mcg
    • 19-50 years: 25 mcg
    • 50 years and older: 20 mcg
  • Pregnant Women
    • 18 years or younger: 29 mcg
    • 19 years and older: 30 mcg
  • Nursing Women
    • 18 years or younger: 44 mcg
    • 19 years and older: 45 mcg
Food Sources

The National Institutes of Health's Office of Dietary Supplements offers this list of food sources for chromium:110

Food Serving size Chromium content
(microgram [mcg])
Broccoli ½ cup 11
Grape juice 1 cup 8
English muffin, whole wheat 1 4
Potatoes, mashed 1 cup 3
Garlic, dried 1 teaspoon 3
Basil, dried 1 tablespoon 2
Beef cubes 3 ounces 2
Orange juice 1 cup 2
Turkey breast 3 ounces 2
Whole wheat bread 2 slices 2
Red wine 5 ounces 1-13
Apple 1 medium 1
Banana 1 medium 1
Green beans ½ cup 1

Chromium is also found in drinking water, especially hard water, but concentrations vary widely. Many good sources of chromium, such as whole wheat, are depleted of this important mineral during processing. The most concentrated sources of chromium are brewer's yeast and calf liver. Two ounces of brewer's yeast or 4 ounces of calf liver supply between 50 mcg and 60 mcg of chromium.

Chromium Deficiency

Some evidence suggests that chromium deficiency may be relatively common.1,86However, this has not been proven, and the matter is greatly complicated by the fact that we lack a good test to identify chromium deficiency.2

Severe chromium deficiency has only been seen in hospitalized individuals receiving nutrition intravenously. Symptoms include problems with blood sugar control that cannot be corrected by insulin alone.

Corticosteroid treatment may cause increased chromium loss in the urine.3 It is possible that this loss of chromium may contribute to corticosteroid-induced diabetes.

Chromium Absorption

Calciumcarbonate interferes with the absorption of chromium.4