Should I Try Chromium Tablets?
I take metformin twice a day and, after breakfast, six or seven supplements I've seen mentioned on TV. Now I've ordered chromium GTF because it's reported to help with blood glucose control. Would you recommend these tablets, especially for those who have heart disease, as I do? John T. Foster, Jr., Jacksonville, Florida
Roger P. Austin, MS, RPH, CDE, responds:
Chromium is an essential trace element that is associated with carbohydrate and lipid (fat) metabolism. Chromium is sometimes referred to as "glucose tolerance factor" (GTF), but GTF is actually a complex of various compounds, of which chromium is thought to be the active component.
Some evidence shows that taking chromium picolinate can decrease blood glucose, insulin levels, and A1C and increase insulin sensitivity in people with type 2 diabetes. But not all the evidence is positive, and some studies have been inconclusive because of their small size or other factors.
There is wide interest among people with diabetes about the role of various dietary supplements, herbs, and other "natural" products that may influence blood glucose levels and diabetic control. However, use of such products is largely a case of "buyer beware." This is primarily a result of a law enacted in 1994 called the Dietary Supplement Health and Education Act (DSHEA). David Kessler, a former commissioner of the Food and Drug Administration (FDA), has said that DSHEA "does not require that dietary supplements be shown [by manufacturers] to be safe or effective before they are marketed. The FDA does not scrutinize a dietary supplement before it enters the marketplace." In other words, the law lets manufacturers market herbal products without having proved their safety and efficacy. The FDA can only remove such products from the market later if problems happen to be detected.
Contrast this with the strict standards by which the FDA scrutinizes any new prescription medication before deciding whether to approve its use in humans. New drugs must be proved both safe and effective in stringent, randomized controlled trials. In such cases, the burden of proof falls on the manufacturer of the new prescription medication. Even with such strict guidelines, some new medications enter the market only to be withdrawn when used on a wider scale than during clinical trials.
There are no such requirements, scrutiny, or protections with dietary supplements such as chromium. Furthermore, there are no regulations assuring uniformity and purity of active-ingredient content, consistency of labeling, or inspection of processing and production facilities. Thus, people who choose to use such products do so at their own risk.