Chromium is an essential mineral found in very low concentrations in the human body. In 1957, researchers discovered that a compound extracted from pork kidney called "glucose tolerance factor (GTF)" helped diabetic rats use insulin more efficiently. (People with diabetes either do not produce enough insulin—a hormone that is needed to convert sugar, starches and other food into energy needed for daily life—or cannot properly use the insulin that their bodies produce. As a result, glucose or sugar builds up in the bloodstream.) Chromium was later identified as the active component of GTF. Today, it is believed that chromium helps insulin bring glucose from the blood into the cells for energy.

As many as 90% of American diets are low in chromium, but few people are deficient in this important mineral. The elderly, people who indulge in strenuous exercise, those who consume excessive amounts of sugary foods, and pregnant women are most likely to be deficient in chromium. Low chromium levels can increase blood sugar, triglycerides (a type of fat) and cholesterol levels and increase the risk for a number of conditions, including diabetes and heart disease.

Studies suggest that chromium supplementation may be helpful for the following conditions:

Diabetes

The benefit of chromium supplements for diabetes has been studied and debated for a number of years. While some studies have shown no beneficial effects of chromium use for people with diabetes, other studies have shown that chromium supplements may reduce blood sugar levels as well as the amount of insulin needed by people with diabetes. Pregnancy-induced and steroid-induced diabetes are thought to benefit from chromium as well. To address the ongoing debate, the National Institutes of Health (NIH) recently called upon researchers to address the safety and effectiveness of chromium for diabetes more fully.

High Cholesterol

Although not all studies agree, chromium has demonstrated the ability to lower total and LDL ("bad") cholesterol levels and raise HDL ("good") cholesterol levels in the blood, particularly in people with high cholesterol.

Obesity

Despite the popularity of chromium for weight loss and even though some studies suggest that chromium may improve lean body mass (namely, muscle) and reduce body fat, its effects are small compared to those of exercise and a well-balanced diet.

Strength Training

Chromium is popular with some body builders and can be found in certain sports nutrition supplements. Despite this popularity, there is little scientific evidence that chromium supplementation changes body composition or helps people gain strength. This topic has been studied in lots of different groups of people, including athletic and nonathletic men and women as well as elderly men.

High Blood Pressure

Animal studies suggest that chromium may help improve blood pressure. This has yet to be tested on people. Until more information is available, use of chromium for this purpose is not currently recommended.

Dietary sources of chromium include brewer's yeast, lean meats (especially processed meats), cheeses, pork kidney, whole-grain breads and cereals, molasses, spices, and some bran cereals.

Brewer's yeast (particularly yeast grown in chromium-rich soil) is a rich dietary source of chromium, as are organ meats, mushroom, oatmeal, prunes, nuts, asparagus, and whole grains and cereals. Vegetables, fruits, and most refined and processed foods (except for processed meats) contain low amounts of chromium.

Chromium is commercially available in several forms including chromium nicotinate, chromium picolinate, chromium-enriched yeast, and chromium chloride. Chromium is available as part of many multivitamins or alone in tablet and capsule forms. Preparation doses are typically between 15 and 200 micrograms (mcg) of chromium per day.

The adequate daily intakes (AI) of dietary chromium are listed below:

Pediatric

• Infants birth to 6 months: 0.2 mcg
• Infants 7 to 12 months: 5.5 mcg
• Children 1 to 3 years: 11 mcg
• Children 4 to 8 years: 15 mcg
• Boys 9 to 13 years: 25 mcg
• Teenage boys 14 to 18 years: 35 mcg
• Girls 9 to 13 years: 21 mcg
• Teenage girls 14 to 18 years: 24 mcg
• Pregnant teenagers 14 to 18 years: 29 mcg
• Breastfeeding teenagers 14 to 18 years: 44 mcg

Adult

• Men 19 to 50 years: 35 mcg
• Men 51 years and older: 30 mcg
• Women 19 to 50 years: 25 mcg
• Women 51 years and older: 20 mcg
• Pregnant women 19 years and older: 30 mcg
• Breastfeeding women 19 years and older: 30 mcg

Dosage for disease prevention and treatment in adults is typically 200 mcg chromium 1 to 3 times a day. Type 2 diabetics may benefit from doses as high as 1,000 mcg /day, but long term safety with such high doses is not known.

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider.

Although the type of chromium found in foods is generally considered safe, extremely high doses of this mineral can inhibit the effectiveness of insulin and cause stomach irritation, itching, and flushing. There have also been rare reports of fast, irregular heart rhythms and liver dysfunction from too much chromium. Two cases of kidney damage have been reported from the use of chromium picolinate supplements.

Dietary chromium, which is considered safe, is often confused with an unsafe industrial form of chromium (hexavalent chromium or chromium VI) that is readily absorbed by the lungs, digestive tract, mucous membranes, and skin. Chromium VI is a toxic industrial compound that is primarily encountered through occupational exposure by either direct contact or through inhalation of dust or aerosols.

If you are currently being treated with any of the following medications, you should not use chromium without first talking to your healthcare provider.

Antacids
Animal studies suggest that antacids, particularly those containing calcium carbonate, may reduce the body's ability to absorb chromium. Although it is unclear how this research relates to people, it may be advisable to avoid taking chromium supplements at the same time as antacids.

Diabetes Medications
Chromium supplements may actually enhance the effectiveness of certain diabetes medications. Clinical studies have demonstrated that people with type 1 or type 2 diabetes who take chromium supplements may require lower doses of insulin, metformin, or sulfonylureas (a group of medications used to treat type 2 diabetes including glimepiride, glyburide, glipizide, and chlorpropamide).

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