Glucosamine isn’t at fault

From Washington, D.C., at a meeting of the American Diabetes Association

According to a new study the popular dietary supplement glucosamine doesn’t cause insulin resistance, the precursor of type 2, or adult onset, diabetes.

Glucosamine, a sugar that’s naturally produced by the body, collects in cartilage and other connective tissue. Millions of people take glucosamine supplements to relieve pain caused by osteoarthritis.

Previous animal and human studies had found that “giving glucosamine can impair insulin’s action, which can potentially make [people] diabetic or worsen diabetes,” says Rajaram J. Karne, now of the Ohio State University Medical Center in Columbus. However, participants in those studies received high doses of glucosamine by injection.

Karne and his colleagues at the National Center for Complementary and Alternative Medicine in Bethesda, Md., tested a commonly used dose of oral glucosamine in 20 normal-weight and 20 obese adults. Each volunteer took a 6-week course of either three 500-milligram pills of glucosamine daily or a placebo. Researchers tested each person’s insulin sensitivity at the beginning and end of the study.

“We’re glad to say that 6 weeks of glucosamine doesn’t make any measurable difference on insulin’s action,” Karne says.