Chondroitin may moderately improve pain in patients with OA compared to placebo, a Cochrane review of the literature concludes. However the authors say many of the trials they reviewed were of low quality and used “unsound” methodology.

The review of 43 randomised trials by the Cochrane musculoskeletal group found chondroitin:

•  may improve pain slightly in the short-term (less than 6 months); – Chondroitin improves knee pain by 20% in slightly more people;

• probably improves quality of life slightly as measured by Lequesne’s index (combined measure of pain, function, and disability);

•  has little or no difference in adverse and serious adverse events versus other agents; and

•  slightly slows down the narrowing of joint space on X-rays of the affected joint.

More high-quality studies are needed to explore the role of chondroitin in the treatment of osteoarthritis, the research group said. The combination of some efficacy and low risk associated with chondroitin may explain its popularity among patients as an over-the-counter supplement, they added.