Chromium is an essential mineral, and although its exact function in the body is unknown, chromium deficiency is associated with abnormal glucose metabolism and decreased insulin sensitivity. Type 2 diabetes is a metabolic disorder in which insulin levels are insufficient to properly regulate glucose metabolism. The elevation in blood glucose levels in people with type 2 diabetes increases the risk of secondary complications including, kidney, eye, nerve and cardiovascular damage. Several recent studies have evaluated the effectiveness of chromium picolinate supplementation for the treatment of type 2 diabetes, and the results are mostly negative.
Glucose Metabolism
An assessment of 15 clinical studies reports that 13 of them demonstrated that chromium picolinate supplementation improves at least one aspect of glucose metabolism in type 2 diabetics, according to the authors of an article in the December 2006 issue of "Diabetes Technology and Therapeutics." Other studies, like the one in the July 2010 issue of "Endocrine Practice," did not observe any effects of chromium picolinate supplementation on blood glucose levels or other markers of impaired glucose metabolism in people at high risk for developing type 2 diabetes.
Insulin Sensitivity
People with type 2 diabetes have insulin resistance, which is a decrease in the sensitivity of tissues like liver and muscle to the actions of insulin. The study in "Endocrine Practice" reports that chromium supplementation at doses of 500 or 1000 mcg per day did not improve insulin sensitivity in people with abnormal glucose metabolism or metabolic syndrome.
Lipid Profile
High cholesterol and lipids compound the symptoms of type 2 diabetes and increase the risk of secondary complications. The Linus Pauling Institute reports that studies examining the effects of chromium picolinate supplementation on lipid profiles and cholesterol levels have produced inconsistent results. This institute concludes that chromium picolinate supplements are only effective in lowering lipids and cholesterol in individuals with a chromium deficiency. A study in a 2007 issue of the "Journal of Cardiometabolic Syndrome" reports that in combination with the B7 vitamin biotin, chromium picolinate supplementation reduced total cholesterol levels and low-density lipoproteins, also called LDLs, but only in type 2 diabetics with high cholesterol levels. Type 2 diabetes is a disease that has many environmental and genetic contributing factors. Chromium deficiency is only one environmental factor that may play a significant role in the disease in a subset population of type 2 diabetics.
Cardiovascular Disease Risk
Cardiovascular disease is much more prevalent in people with type 2 diabetes than in those who do not have the disease. No studies have yet evaluated the preventative action of chromium picolinate supplementation on the risk of developing cardiovascular disease. However, a study in the September 2004 issue of "Diabetes Care" notes that heart disease is higher in type 2 diabetic men with lower levels of chromium in their bodies. This association may be linked to the fact that people with type 2 diabetes and heart disease often have impaired kidney function, leading to excessive excretion of chromium.
Weight Loss
An assessment of more than 10 clinical trials published in the April 2003 issue of the "International Journal of Obesity and Related Metabolic Disorders" concludes that chromium picolinate supplementation is associated with a very minor decrease in body weight, amounting to less than 2.5 lb.
References
- PubMed.gov: 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; Ather Ali et al.; July 2010
- PubMed.gov: Combination of Chromium and Biotin Improves Coronary Risk Factors in Hypercholesterolemic Type 2 Diabetes Mellitus: A Placebo-Controlled, Double-Blind Randomized Clinical Trial
- "Diabetes Care"; Lower Toenail Chromium in Men With Diabetes and Cardiovascular Disease Compared With Healthy Men; Swapnil Rajpathak et al.; September 2004
- The Linus Pauling Institute: Chromium
- PubMed.gov: Chromium Picolinate for Reducing Body Weight: Meta-Analysis of Randomized Trials
