Investigation into popular dietary supplement starts

Researchers at US Cedars-Sinai Medical Centre are currently enrolling patients in a large multi-centre clinical trial to determine whether two popular dietary supplements - glucosamine and chondroitin sulfate - reduce the knee pain associated with osteoarthritis (OA). The disease causes pain, deformity and enlargement of the joints and is diagnosed in almost twice as many women as men. "This study is the first and largest of its kind to evaluate whether these popular supplements actually work to alleviate knee pain in people afflicted with this disease,"said Michael Weisman, M.D., Principal Investigator and Director of the Division of Rheumatology at Cedars-Sinai Medical Center. Marketed as dietary supplements, glucosamine and chondroitin sulfate have been widely reported as effective alternative treatments for arthritis. For the last two decades, the supplements have been used extensively in Europe to treat OA. Glucosamine is a substance in thebody that helps to form cartilage. Chondroitin sulfate is part of a large protein molecule that gives cartilage its elasticity. Both glucosamine and chondroitin sulfate are believed to play a role in cartilage maintenance and repair. To date the majority of studies examining the effectiveness of glucosamine and chondroitin sulfate to reduce OA knee pain were conducted in Europe. To investigate the safety and efficacy issues of these supplements the National Institutes of Health recently launched a $6.6 million dollar study. The study aims to recruit more than 1,000 patients at nine centers across the country.