Trivalent chromium is a trace mineral widely used as a dietary supplement. Chromium absorption in the gut is low, but combining it with picolinate increases its absorption. The National Academy of Sciences estimates safe and adequate dietary intake for trivalent chromium is at levels between 50 and 200 micrograms per day.
Mechanism of Action
The Office of Dietary Supplements, or ODS, reports that chromium deficiency can cause insulin resistance and elevations in blood glucose levels, although this is a rare phenomenon. The precise mechanism on how chromium influences glucose, protein and fat metabolism is unknown. A review article in "Diabetes and Metabolism" reports that chromium increases the actions of the hormone insulin, leading to increased insulin sensitivity. Therefore, in the presence of chromium, less insulin would be required to elicit the same cellular response.
Type 1 Diabetes
The majority of studies that have looked at the effectiveness of chromium supplementation as an antidiabetic agent have been in Type 2 diabetics, but a few small-scale studies exist in Type 1 diabetics. A review article in "Diabetes and Metabolism" reports Type 1 diabetics who took chromium supplements for 10 days were able to reduce their insulin dosage and had improved blood glucose control. This source also described a case report, in which average blood glucose levels were significantly reduced in a Type 1 diabetic woman treated with chromium supplements for three months.
Type 2 Diabetes
A review study of several clinical trials in the journal "Diabetes Technology and Therapeutics" concludes there is much evidence to support chromium picolonate supplementation reduces blood glucose and insulin levels in Type 2 diabetics. However, a well-controlled study in the March 2005 issue of "Diabetes Care" reports that, at doses of 800 micrograms per day, chromium picolinate did not significantly affect glucose tolerance, insulin resistance or lipid profiles in people with impaired glucose metabolism . The ODS reports there is still much controversy over the therapeutic benefit of chromium picolinate. The study in the July 2010 issue of "Endocrine Practice" reports chromium picolinate supplementation did not improve glucose metabolism or decrease the risk of acquiring Type 2 diabetes in patients at high risk for the disease.
Weight Loss
The effectiveness of chromium picolinate supplementation for weight loss is also heavily debated. The ODS reports a review of 24 studies that examined the effects of chromium picolinate at doses up to 1,000 micrograms per day found no significant benefits on lipid profiles or weight loss.
Safety
The Environmental Protection Agency established a reference dose of 1.5 mg per kg per day for trivalent chromium. This is equivalent to 105 mg/day for a person weighing 70 kg and is greater than 100 times the average supplement dose. The reference dose refers to the amount of a substance a person can be exposed to daily without having a significant risk for adverse effects.
References
- Office of Dietary Supplements: Chromium
- Diabetes Care: Chromium Supplementation Does Not Improve Glucose Tolerance, Insulin Sensitivity, or Lipid Profile
- Diabetes Technology and Therapeutics: Clinical Studies on Chromium Picolinate Supplementation in Diabetes Mellitus--A Review
- Endocrine Practice: Chromium Effects on Glucose Tolerance and Insulin Sensitivity in People at Risk for Diabetes
- Diabetes and Metabolism: Chromium in the Prevention and Control of Diabetes
