Glucosamine Stops Knee Arthritis in Women
Supplement Likely Benefits All Types of People, All Joints, Say Researchers
"There is certainly a good reason to believe that estrogens are important for cartilage, and this continues to be an active area of interest -- determining exactly how menopause impacts osteoarthritis," says John H. Klippel, MD, head of the Arthritis Foundation.
"What's really unique about this study is that they are able to look at a relatively homogeneous population -- postmenopausal women, as opposed to the whole world of osteoarthritis -- and have been able to confirm that in this population, glucosamine improves function and retards (measurable disease) progression."
All Joints Can Benefit
Rovati says his findings are the latest to show what his research team has long suspected: "Based on our studies and others, it appears that everyone with knee osteoarthritis can benefit from glucosamine sulfate," he tells WebMD. "And we suspect that this data can be transferable to all weight-bearing joints. The reason we and others primarily study knee osteoarthritis is because it's the most common type and there are more patients."
Glucosamine is naturally produced by the body and found primarily in joint cartilage, where it's believed to help maintain joint health and resilience. Although glucosamine supplements have long enjoyed a reputation for easing knee pain, only recently have they garnered convincing scientific evidence to back up these claims.
These supplements, which are not regulated by the FDA, contain glucosamine extracted from tissues of shellfish. They come in two forms: glucosamine sulfate, like that used in Rovati's studies, and glucosamine hydrochloride.
"The difference between the two is the added salts used," says Klippel, former clinical director of the National Institute of Arthritis and Musculoskeletal and Skin Diseases. "Glucosamine is the active ingredient, so one would suspect a similar result from either type." The prescription product used in Rovati's study is chemically similar to glucosamine sulfate products sold in the U.S., but did not contain chondroitin or methylsulfonylmethane (MSM), as many do.
Still, Klippel tells WebMD that there is no evidence to indicate that glucosamine should be taken as a preventative measure before menopause onset, to reduce a woman's later risk of knee problems. "On the other hand, this study confirms that if you already have osteoarthritis, taking glucosamine may be a good thing to do."
But it may not be enough: "Although glucosamine may be helpful, it's also part of a much larger treatment plan -- and that should include weight management and physical activity," says Klippel. "Both are important, not only to reduce the risk of osteoarthritis, but also reducing symptoms once it has been diagnosed."