The safety and efficacy of high-dose chromium - High-Dose Chromium

Alternative Medicine Review, June, 2002 by Davis W. Lamson, Steven M. Plaza

A blinded crossover study found that a nicotinic acid-complexed form of trivalent chromium at 200 mcg/day slightly lowered fasting total and LDL cholesterol, triglycerides, glucose concentrations, and 90-minute postprandial glucose levels in individuals with type 2 diabetes. However, the authors did not regard the results as statistically significant. (32) A study of 26 non-obese young adults using chromium as picolinate (220 mcg/day Cr III) showed no reduction in total cholesterol after 90 days. (33) In a contrasting study of 23 male athletes, it was found that supplementation with either 200 or 800 mcg/day of Cr III as chromium nicotinate produced sizeable decreases in total cholesterol and LDL cholesterol, with some reduction in HDL cholesterol. There was demonstration of a dose-response relationship. (34) In another study using an inorganic form of chromium III (chromium chloride) for 76 patients with established atherosclerosis, doses of 250 mcg/day were not shown to decrease total cholesterol levels while triglycerides decreased, HDL cholesterol increased, and VLDL continued to decrease over the 7-16 month period. (35) In this study triglycerides did not fall significantly within the first three months of supplementation; therefore, longer periods of time and/or higher doses may be required to see a triglyceride-lowering effect.

Perhaps the most significant data on the reduction of cholesterol attributable to chromium supplementation is demonstrated in the 1997 study by Anderson et al (22) of 180 individuals with type 2 diabetes using either 200 mcg/day or 1000 mcg/ day of Cr III as chromium picolinate. There were no significant effects of chromium supplementation on HDL cholesterol or triglycerides. Examination of the graphs in the paper indicates little difference in total cholesterol over four months in the 200 mcg/day supplementation group. However, total cholesterol appeared to drop steadily during the four-month period in the 1000 mcg/day group. In summary, there appears to be evidence that chromium supplementation can lower serum cholesterol, but it may require a longer time or higher doses of chromium with diabetic patients.

Chromium, DHEA, and Osteoporosis

A placebo-controlled trial of 27 postmenopausal women given 200 mcg/day of chromium as picolinate for 60 days found a decrease in insulin levels (38%), plasma glucose (26%), and urinary calcium (19%), while dehydroepiandrosterone (DHEA) levels increased by 24 percent. The authors suggest that a 47-percent decrease in urinary hydroxyproline/creatinine ratio indicates that chromium might be effective in the prevention of osteoporosis. (36)

Chromium Dosage Criteria

The U.S. Environmental Protection Agency (EPA) has replaced acceptable daily intake (ADI) with calculated reference dose (RfD). The RfD is calculated from the No Observed Adverse Effect Level (NOEL) or the Lowest Observed Effect Level (LOAEL) from animal or human experiments. From this data, safety factors are applied consisting of "uncertainty factors" and a "modifying factor." (37) The RfD has been calculated for Cr III at 70 mg per day, reflecting the weight of a 70 kg man at a rounded per kg dosage of 1 mg from the actual RfD of 1.47 mg/kg. The RfD reflects a staggering 350 times the Estimated Safe and Adequate Daily Dietary Intake (ESADDI) of 50-200 mcg. (37) The ratio of RfD to ESADDI is less than 2 for zinc, about 2 for manganese, and about 6 for selenium as compared to 350 for chromium. (38) The ESADDI value for chromium has been criticized for the arbitrary "safe and adequate" dosage being 350 times less than that of the RfD, given the lack of toxicity or adverse effects of Cr III. (37,38) This suggests dietary supplementation may be greatly underdosed.