Chromium is an essential trace element involved with proper metabolism of carbohydrates and lipids in the body. Chromium supplements may be useful in a number of health conditions: even though chromium is needed in only small amounts, it is a key mineral in the body.
Chromium is a difficult mineral to absorb. Figures range from 0.5-3% absorption for the inorganic chromium salts often found in food. The organic complexes of chromium, such as glucose tolerance factor (GTF), are absorbed better, at about 10-20%. The kidneys clear any excess from the blood, while much of chromium intake is eliminated through the feces. This mineral is stored in many parts of the body, including the skin, fat, brain, muscles, spleen, kidneys, and testes.
Food refinement and the loss of topsoil through poor agricultural practices reduce the level of chromium in foods. The process of refining removes chromium from grains. As a result, foods such as white flour and white rice are low in chromium. Most Americans get only 50-100mcg of chromium per day through diet.
There are, however, still many good food sources. Since GTF is better absorbed than inorganic chromium, the level and activity of GTF in foods affects how well they supply us with this mineral. GTF activity may not always correspond to the actual amount of chromium in foods; however, many foods with good GTF activity also have good amounts of chromium. Hard water often contains some chromium; it may supply up to half of the daily needs of an adult.
Brewer's yeast is likely the best available source of chromium as well as having the highest GTF activity. About two tablespoons, or six tablets, per day supply most of our chromium needs; however, many people – perhaps 30-40% – do not tolerate yeast very well and find that it causes digestive upset or bloating. If yeast is tolerated, it supplies a great many nutrients and is a low-calorie and low-fat source.
Following yeast in chromium concentration are beef, liver, whole wheat, rye, fresh chilies, oysters, potatoes, wheat germ, green peppers, eggs, chicken, apples, butter, bananas, and spinach. Yeast (44ppm), black pepper (10ppm), and molasses (2ppm) are good sources of chromium, but since they are usually consumed in small quantities, it is best to have other chromium foods in the diet. In general, the whole grains, meats, shellfish, chicken, wheat germ and bran, and many vegetables, especially potato skins, are adequate sources. Beets and mushrooms may contain chromium.
There are many chromium supplements available. Chromium is available in supplements under the names chromium picolinate, chromium polynicotinate, chromium chloride and others. These supplements have gained a great deal of attention as a means to lose weight. More research is needed to confirm any results to date.
Chromium supplements are either niacin-bound (preferred) or salt based; and may be included in weightloss, cholesterol reducing, or insulin (pancreas) supporting products. Niacin-bound chromium is now available yeast-free.
The brain is highly dependent on glucose as an energy substrate. A drop in blood glucose levels may result in the release of regulatory hormones, i.e. epinephrine, glucagon, cortisol, and growth hormone. Chronic and gradual decreases in blood sugar results in a gradual increase in these regulatory hormones which leads to symptoms of dizziness, headache, clouding of vision, mental acuity, emotional instability, confusion, and abnormal behavior.
As a part of Glucose Tolerant Factor (GTF), chromium assists insulin in its ability to regulate glucose levels in the blood. GTF, a niacin bound chromium found most commonly in brewer's yeast, has been shown to lower cholesterol levels when taken as a supplement.
Research has further demonstrated that insulin is transported through the blood-brain barrier and influences brain function via widely distributed receptors and neurons. Chromium is known to enhance the action of insulin and facilitate the uptake of blood sugar into cells. This is important considering that the average western diet is chromium deficient with 2 out of every 3 American being hypoglycemic.
Investigators have revealed that psychiatric patients do have higher incidences of hypoglycemia and the correction of any underlying aberrant glucose metabolism is the first step in treating this group.
Chromium supplementation may be efficacious in the treatment of depression as seen in anecdotal reports of improved mood in clinical depressives receiving chromium picolinate.
As one ages, the ability to absorb chromium decreases. Since there is no US RDA for chromium, many of the elderly population may be ingesting inadequate amounts of chromium in their diet. The deficiency limits for chromium are thought to be around 50mcg/day.
Chromium is often deficient in those with atherosclerosis; supplementation may result in plaque regression. Chromium is used to help reduce atherosclerosis, especially in those who show low chromium levels. Cultures with higher tissue levels of chromium also appear to have lower incidences of atherosclerosis and heart disease. Dosage: 200mcg/day.
Chromium recently has been shown to lower blood cholesterol while mildly raising HDL (high-density lipoprotein), the good portion of cholesterol. This lowers the risk ratio for coronary artery disease.
Chromium picolinate supplementation at 1,000mcg per day over a 13-week period combined with exercise decreased total cholesterol, LDL cholesterol and insulin levels in a recent small study of both males and females. [J Nutr Biochem, 1998;9: pp.471-475]
Henry Schroeder, MD, who has done numerous studies with chromium, has shown that 2mg of inorganic chromium given daily reduced cholesterol levels by about 15%.
Chromium picolinate supplementation at 1,000mcg per day over a 13-week period combined with exercise decreased total cholesterol, LDL cholesterol and insulin levels in a recent small study of both males and females. [J Nutr Biochem, 1998;9: pp.471-5]
A 3-month double-blind study of 122 moderately overweight people found that 400mcg of chromium daily resulted in an average loss of 6.2 pounds (2.8kg) of body fat, as opposed to 3.4 pounds (1.5kg) in the placebo group. There was no loss of lean body mass. These results suggest that chromium can help you lose fat without losing muscle.
However, six smaller double-blind placebo-controlled studies found chromium picolinate supplements produced no weight loss or change in lean body mass. These conflicting results may be due to differences in study size, the dosage of chromium, and the individuals enrolled. Overall, chromium does appear to be promising.
Chromium picolinate helps to promote conversion of tryptophan to serotonin. It accomplishes this by facilitating absorption into muscle tissue of the amino acids that compete with tryptophan for access to the brain.
Chromium combines with niacin to form Gluten Tolerance Factor (GTF), which works with insulin to help the body use glucose. Insulin is the hormone that takes glucose from blood and puts it into cells where it is used for energy. Chromium helps reduce the amount of insulin needed to maintain blood sugar. Some studies report that people who have diabetes can get better glucose control by taking chromium supplements.
Chromium and GTF are used in the treatment of both hypoglycemia and diabetes mellitus, two problems of blood sugar utilization and metabolism. Preventing chromium deficiency is the key here. The earlier treatment is begun, especially with potential diabetes, the more helpful it may be. Preformed GTF is not readily available, though formulas that contain all of its components seem to work better than chromium alone, and small amounts given daily have been shown to both increase glucose tolerance and decrease blood fats, both cholesterol and triglycerides, as well as to raise HDL. Chromium also does this and has been used along with niacin (also a part of GTF) in the treatment of high blood cholesterol.