Bottom Line: Chromium may help to regulate blood glucose in some people, but the long-term effects are not known. There is no clear evidence to show that chromium supplementation is effective for building muscle mass or for losing weight. Chromium is an element required by the body in very small amounts (0.025 mg a day). Adequate amounts are usually obtained in the diet from foods such as American cheese, meat, fish, fruits, and whole grains. Based on laboratory experiments, scientists think that chromium is involved in maintaining adequate levels of glucose, fats, and insulin activity in the body. Chromium may interact with insulin receptors and enhances the effects of insulin on cells, including improved glucose uptake. In theory, this could help patients with type 2 diabetes.
Chromium is sometimes combined with GTF (Glucose Tolerance Factor) in over-the-counter products. GTF is a yeast extract that helps with glucose metabolism in laboratory studies, but this effect has not been confirmed in humans.
To treat diabetes Clinical trials produced conflicting results regarding chromium's ability to lower blood glucose, cholesterol, and triglycerides. According to the FDA, it is highly uncertain that chromium picolinate can reduce the risk of insulin resistance or type 2 diabetes.
To improve muscle mass Clinical trials do not support this use.
To improve weight loss Clinical trials do not support this use.
Weight loss and muscle gain: Several clinical trials have tested chromium supplements to see whether they are effective for losing weight and gaining muscle mass. However, most of these clinical trials were small and had mixed results. Right now, no clinical trial supports the use of chromium supplements for weight loss or improvements in muscle mass.
Type 2 diabetes: The use of chromium supplements for treating type 2 diabetes was tested in a randomized controlled trial. For four months, 180 patients took either 100 micrograms of chromium, 500 micrograms of chromium, or a placebo pill twice daily. Both of the groups taking chromium had lower fasting glucose and postprandial (after eating) blood glucose levels than the placebo group. This suggests that chromium is helpful in reducing blood glucose levels in patients with type 2 diabetes, but this study did not address the long-term effects of chromium, and what happens when it is discontinued in these patients.
According to the FDA, it is 'highly uncertain' that chromium picolinate reduces the risk of insulin resistance and type 2 diabetes.
Because studies about chromium supplementation in patients with type 2 diabetes have produced mixed results, researches wanted to see if certain characteristics of the patient (e.g., age, race, weight, etc.) influenced their response to chromium. At the beginning of the study, many characteristics (baseline characteristics) were measured in 73 patients with type 2 diabetes. These patients then received either chromium picolinate (1000 ìg/day) or placebo. After 6 months, the patient characteristics were again measured. The only characteristic that could predict if a patient would respond to chromium was insulin resistance at the beginning of the study. This suggests that patients with insulin resistance are more likely to benefit from chromium supplementation that those without it. However, larger studies are needed to identify other factors that may influence a patient's response to chromium.
This product is regulated by the FDA as a dietary supplement. Unlike approved drugs, supplements are not required to be manufactured under specific standardized conditions. This product may not contain the labeled amount or may be contaminated. In addition, it may not have been tested for safety or effectiveness.
You are taking sulfonylureas or insulin (in theory, chromium may lower your blood sugar even more. Diabetics may wish to check their blood glucose levels more often so that adjustments can be made to their therapy, if necessary. Ask your doctor.)
The following cases of very rare side effects have been reported:(1) Two people had kidney failure, (2) One patient developed acute generalized exanthematous pustulosis (red skin lesions, fever, edema, high white blood cell count, and elevated blood eosinophil levels), (3) One patient developed rhabdomyolysis (destruction of skeletal muscle)while taking chromium picolinate in addition to other dietary supplements (so whether chromium caused this condition is not clear).
When taken by mouth, chromium is poorly absorbed through the gut into the bloodstream. The salt forms of chromium, such as chromium picolinate, niacin-bound chromium, and chromium chloride are more readily absorbed.
Chromium is a trace element that is necessary for glucose and lipid metabolism in humans. Most people consume adequate amounts through their diet and deficiency is rare. Patients take Chromium supplements for diabetes, weight loss, and to improve muscle mass. Chromium is poorly absorbed following oral administration, but the salt forms (e.g., chromium picolinate, niacin-bound chromium, and chromium chloride) appear to have better bioavailability. It plays a role in insulin metabolism (1)(2). Whether chromium affects weight loss or muscle mass improvement is unclear, although one study showed that it may increase satiety (3). Chromium supplementation with biotin may help to improve glycemic control in type 2 diabetics (10)(12). Some commercial products have chromium with GTF (Glucose Tolerance Factor), an extract from yeast, to facilitate glucose metabolism (19). However, its effect in humans is inconclusive. Other studies also suggest conflicting results (13). Due to inconsistencies concerning chromium picolinate supplementation and glucose metabolism, the FDA states that chromium picolinate does not reduce the risk of insulin resistance or type 2 diabetes (11). Reported adverse effects include sporadic case reports of renal failure (14)(15), rhabdomyolysis (16), liver damage (17), and dermatitis (18). Chromium requires transferrin to be absorbed and is eliminated renally (17); therefore, patients with renal and hepatic dysfunction should not be routinely supplemented. Optimal chromium dosage remains undetermined.
Chromium is an essential trace element involved with glucose and lipid metabolism, circulating insulin levels, and the peripheral activity of insulin (1). In vitro and in vivo studies suggest that chromium potentiates the activity of insulin (14). This is thought to occur via enhanced intracellular tyrosine kinase activity that results from an interaction between chromium, low molecular weight chromium-binding substance, and activated cell surface insulin receptors (2).
Absorption: The bioavailability of trivalent chromium is relatively low, ranging from 0.4 to 2.5% of the orally administered dose. Chromium picolinate, trivalent chromium bound to picolinic acid, has a bioavailability of approximately 3%. Distribution: Trivalent chromium binds to transferrin and albumin. It distributes throughout the body, but appears to concentrate in the kidney, liver, soft tissue, and spleen. Chromium fits a three compartment pharmacokinetic model. Excretion: The biological half-life for urinary excretion of chromium ranges from 0.97-1.51 days. Unabsorbed chromium is excreted in the feces while absorbed chromium is primarily eliminated renally.
Rare: Hepatic toxicity (12) Case reports: Two cases of renal failure (9)(10); one case of acute generalized exanthematous pustulosis, characterized by erythematous lesions, fever, edema, leukocytosis, and eosinophilia (13); one report of rhabdomyolysis in a patient taking chromium picolinate in addition to other dietary supplements (11).
Several clinical trials have evaluated the efficacy of chromium supplementation for weight loss and muscle mass (4), (16)-(21). Most trials had small sample sizes and conclusive data is lacking. To date, no study supports the use of chromium supplements for weight loss or improvements in muscle mass.
Wang ZQ, et al. Phenotype of subjects with type 2 diabetes mellitus may determine clinical response to chromium supplementation. Metabolism. Dec 2007;56(12):1652-165. Because the effects of chromium supplementation in patients with type 2 diabetes have been inconsistent, the aim of this study was to determine if metabolic or clinical characteristics influenced the patient's response to chromium. In this randomized, double-blind, placebo-controlled study, baseline measures, including insulin sensitivity, were taken after which 73 patients received either chromium picolinate (1000 ìg/day) or placebo. After 6 months, study parameters were again measured and any relationship between the baseline characteristics and changes in insulin sensitivity were determined. Baseline insulin resistance was the only characteristic associated with response to chromium. However, because baseline insulin resistance accounted for approximately 40% of the variance in response to chromium, further studies are required to identify other factors that may influence response to chromium.
Anderson RA, et al. Elevated intakes of supplemental chromium improve glucose and insulin variable in individuals with type 2 diabetes. Diabetes 1997;46:1786-91. A prospective, double-blind, randomized evaluation of chromium supplementation in type 2 diabetic patients ages 35-65 years. A total of 180 patients were randomized to 4 months of placebo, 100 mcg chromium twice daily, or 500 mcg chromium twice daily. Primary outcomes measured were change in fasting glucose, hemoglobin A1c, fasting insulin, and 2 hour post prandial glucose levels. The authors report that patients receiving 500 mcg chromium twice daily had statistically significant lower fasting glucose and 2 hour post prandial glucose levels at 2 and 4 months. Both treatment groups had significantly lower fasting and 2 hours post prandial insulin levels at 2 and 4 months, and hemoglobin A1c levels at four months decreased by 1-2 grams per deciliter in each treatment group. The authors did not publish actual baseline values and the statistical methods used are questionable. No adverse events were reported. The long-term effect and withdrawal of chromium supplementation is not addressed.
Pasman WJ, et al. The effectiveness of long-term supplementation of carbohydrate, chromium, fibre and caffeine on weight maintenance. Int J Obes Rel Metab Dis 1997;21:1143-51.
