Submitted to: Nutrition Research Reviews
Publication Type: Review Article
Publication Acceptance Date: March 20, 2002
Publication Date: June 1, 2003
Citation: Anderson, R.A. 2003. Chromium and insulin resistance. Nutrition Research Reviews. Technical Abstract: Insulin resistance leads to the inability of insulin to control the utilization and storage of glucose. It is associated initially with elevated levels of circulating insulin followed by glucose intolerance which may progress to type 2 diabetes, hyperlipidemia, hypertension, obesity and cardiovascular diseases. While the causes of these diseases are multifactoral, one nutrient that is associated with all of these abnormalities is chromium. In the presence of chromium, in a biologically active form, much lower levels of insulin are required. Modern diets, which are often high in refined carbohydrates, are not only low in chromium, but lead to enhanced chromium losses. In response to the consumption of refined carbohydrates, there is a rapid rise in blood sugar leading to elevations in insulin that cause a mobilization of chromium. Once mobilized, chromium is not reabsorbed but lost via the urine leading to decreased chromium stores. Several studies involving both humans and experimental animals have reported improvements in insulin sensitivity, blood glucose, insulin, lipids, hemoglobin A1C, lean body mass and related variables in response to improved chromium nutrition. However, not all studies have reported beneficial effects associated with improved chromium nutrition. Well-controlled human studies are needed to document an unequivocal effect of Cr on insulin sensitivity in humans. Studies need to involve a significant number of people with insulin resistance, glucose intolerance or early stages of diabetes, who have not been taking supplements containing Cr for at least four months, and involve at least 400 to 600 g of supplemental Cr daily or more. Studies should be of at least four months to document sustained effects of supplemental Cr on insulin resistance and related variables. Chromium is a nutrient and not a therapeutic agent and therefore will only be of benefit to those whose problems are due to suoptimal intake of chromium.