Researchers Draw Positive Conclusions on Dietary Supplements for Arthritis

WASHINGTON, D.C., March 15, 2000—Two recent independent meta-analyses found that chondroitin and glucosamine are effective in relieving the symptoms of osteoarthritis (OA). OA is the most common form of arthritis, affecting an estimated 12 percent of the U.S. population.

A meta-analysis by researchers from Boston University School of Medicine, published in the March 15 issue of the Journal of the American Medical Association, examined 15 studies that investigated the effect of chondroitin and/or glucosamine on osteoarthritis of the hip or knee. All the studies were randomized, double-blinded, placebo-controlled and tested the treatment for four weeks or longer.

John Cardellina, Ph.D., vice-president of botanical science and regulatory affairs at the Council for Responsible Nutrition noted, "The promising news from this meta-analysis is that even after rigorous adjustment for possible flaws and biases in the studies, chondroitin and glucosamine were found effective." The researchers concluded, "because of their safety, these remedies would have great utility in the treatment of OA, even if they were only modestly effective.

Another meta-analysis of controlled clinical trials, reported in the January issue of the Journal of Rheumatology, similarly examined the efficacy of chondroitin sulfate in the treatment of OA. This meta-analysis included seven trials, with treatment duration from 3 to 12 months. In all seven trials, chondroitin sulfate was found to be significantly superior to placebo in relieving OA symptoms.

Authors of both meta-analyses called for large, long-term studies to confirm the safety and efficacy of glucosamine and chondroitin. The National Institutes of Health is sponsoring such a study, with subject recruitment beginning later this year. The double-blind, randomized trial will test four treatments for 16 weeks. Patients will receive 500 milligrams (mg) of glucosamine sulfate 3 times per day, 400 mg of chondroitin sulfate 3 times per day, a combination of glucosamine and chondroitin, or placebo.

"The results of the two meta-analyses are very exciting," said Dr. Cardellina. "The findings indicate that glucosamine and chondroitin provide safe, therapeutic benefit for relieving the symptoms of osteoarthritis."