Chromium facilitates the binding of insulin to cell membranes, thus playing a crucial role in promoting normal glucose tolerance.
Absorption and Excretion
Chromium is absorbed in small amounts in the intestine. It is transported by transferrin primarily to the bone. Vitamin C has been shown to enhance uptake of chromium. Chromium is excreted in the feces.
Chromium deficiency has been seen in hospitalized patients who did not receive supplemental chromium in their total parental nutrition. Stress, such as in trauma, has been shown to increase excretion of chromium.
The estimated safe and adequate daily dietary intake of chromium is in the range of 50 to 200 mcg for adults. For infants the safe dosage ranges from 10 to 60 mcg per day and for children, 20 to 200.
Whole grains, cereals, and processed meats are good sources of chromium.
Chromium in the form of chromium picolinate has been used by weightlifters for muscle building, and as a weight loss agent. Research has not consistently substantiated its proclaimed effects on muscle mass or body fat. Supplemental doses are usually in the range of 400 to 600 mcg per day.
Toxicity of chromium has not been a clearly documented problem. It has been proven that high exposure to chromium in stainless steel welders is associated with pulmonary cancer.