Amount of drink consumed, overall diet, and exercise frequency were not controlled. After 72 days, underwater displacement testing showed significantly reduced body fat in the chromium groups compared to placebo, but no significant difference between the two chromium groups. ![]() 10 Subjects were instructed to consume "at least two servings" of a protein drink containing their assigned chromium dose. In the first, 154 adults were divided into three groups and received 0 mcg, 200 mcg, or 400 mcg chromium picolinate daily. Two randomized, double-blind trials found positive effects from chromium supplementation, yet both had methodologic flaws that call their results into question. Additionally, four other studies focused primarily on diabetic outcomes and found no changes in body composition. For this update, six more studies of chromium for weight loss were found: two with positive results, three with negative results, and one with mixed results. The 1998 review found one 1969 study reporting increased fat-free body mass and decreased body fat after chromium supplementation, and five studies reporting no significant benefits. 8 Chromium supplementation allegedly reverses these effects, leading to the "burning" of excess fat, weight loss, and increased muscle mass.Ĭlinical studies prior to 1998 were reviewed here previously 9 it should be noted that chromium doses are reported in mcg, where 1 mcg = 0.001 mg. Insulin resistance also hinders the passage of amino acids into muscle cells, reducing protein synthesis. 7 Less glucose enters cells for energy production and instead is stored as fat. In contrast, "chromium deficiency" leaves cells desensitized to insulin (or "insulin resistant"). ![]() This enzyme enhances glucose absorption and promotes fatty acid metabolism. 1 The resulting complex then activates an enzyme called insulin receptor tyrosine kinase. This allows these cells to absorb chromium which then binds a small protein (chromodulin) inside the cell. Normally, receptors on the surfaces of insulin-sensitive cells bind insulin. 6 Because many overweight patients with type 2 diabetes can control their diabetes with effective weight management, and because chromium’s mechanism of action involves glucose and insulin metabolism, there is interest in chromium as a weight loss agent. 5 Research on the potentially beneficial role of chromium in treating type 2 diabetes in chromium-deficient patients was reviewed here previously. 4 There is no simple, reliable test for chromium deficiency.Ĭhromium deficiency was first reported in 1977 when patients on long-term total parenteral nutrition developed classic diabetic symptoms that were reversed with the addition of chromium to their diets. 4 Clinical research is hampered by the analytical challenges of accurately measuring chromium levels, since only 0.5-2% of chromium in dietary sources is absorbed, and urinary levels occur in parts per billion. A small number of studies have found little detriment from people consuming 15 or 25 mcg/d. The AI level for chromium is 35 mcg/d for young men and 25 mcg/d for young women. 4 In their place are Adequate Intake (AI) levels, which are the amounts expected to meet or exceed the daily requirements in essentially all healthy people. 3 The Institute of Medicine (IOM) 2001 report on Dietary Reference Intakes concluded there was insufficient evidence to set an Estimated Average Requirement or a Tolerable Upper Intake Level (UL) for chromium. ![]() 3 The USDA estimated safe and adequate daily dietary intake of chromium is 50-200 mcg for adults. 2 Clinicians likely will receive more inquiries about the effectiveness and safety of chromium as a viable weight-loss alternative to the pharmaceuticals that remain, such as phentermine and sibutramine (Meridia ®).Ĭhromium is an essential trace element and part of the insulin metabolic pathway. ![]() The November 2000 Food and Drug Administration (FDA) recommendation to withdraw phenylpropanolamine, present in popular over-the-counter weight-loss medications and associated with stroke, is a more recent reminder of the danger of these medications. Physicians have not yet warmed to prescription pharmacological approaches to dieting, after the 1997 withdrawals of fenfluramine and dexfenfluramine, both associated with valvular regurgitation and primary pulmonary hypertension. The supplement also allegedly increases energy, curbs addictions, cures acne, prevents insomnia, relieves depression, and increases life span. 1 Chromium picolinate is promoted as a "fat burner" and "muscle builder" for losing weight and enhancing athletic performance. Sales of chromium supplements generate more than $100 million annually.
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