Chromium enables insulin (which controls blood sugar levels) to function and helps in the processing (metabolism) and storage of carbohydrates, protein, and fat. Experts have not yet determined whether chromium supplements are useful for people with diabetes. People with diabetes should not take chromium supplements unless they are supervised by a diabetes expert.
Only a small amount of the chromium in food is absorbed. Chromium is absorbed better when eaten with foods that contain vitamin C and niacin. Supplements do not enhance muscle size or strength in men.
Chromium deficiency is rare in developed countries and usually results from intravenous feeding (total parenteral nutrition) used for a long time.
Symptoms may include weight loss, confusion, impaired coordination, and a reduced response to sugar (glucose) in blood, increasing the risk of diabetes. Treatment may involve chromium supplements.
Small amounts of chromium taken by mouth are not harmful (toxic). In the workplace, people may be exposed to a different, toxic form of chromium. This form results from industrial pollution. This form may irritate the skin, cartilage of the nose, lungs, and digestive tract and may cause lung cancer.
Last full review/revision June 2013 by Larry E. Johnson, MD, PhD