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by Danielle Clarke-Fox, DPT

Over the past several years there has been quite a discussion in the medical community regarding glucosamine and chondroitin sulfate supplements. I hear so many patients talking about whether or not to take the supplement and asking me what they should do. So here’s the low down on the supplements and their progress in clinical trials.

Let’s start with a short overview of the arthritic process in discussion as well as the basics of glucosamine and chondroitin themselves. These supplements are being studied in the improvement of pain, joint space integrity and cartilage quality of major joints such as the knee and hip in cases of osteoarthritis. Glucosamine is an amino sugar found in and around the cartilage cells. The body produces glucosamine and sends it to connective tissue and areas of the body populated with cartilage.

Chondroitin is a separate substance from glucosamine, they are often bundled together for purpose of supplementation but can also be purchased separately. Chondroitin sulfate in the simpliest terms is a chain of types of sugars, the technical term is glycosaminoglycan. It functions as a structural component of cartilage, helping to resist compression forces, which would narrow the joint spaces. It is manufactered from sources such as shark and cow cartilage.

The theory behind taking these supplements and frequently combining them together is that the body will be more apt to build and repair cartilage if more of these building blocks are available for use.

One of the most recent and well-referenced studies was performed by a branch of the National Institute of Health known as the National Center for Alternative and Complementary Medicine. This study utilized a large sample size; pitted placebo vs celecoxib vs glucosamine with chondroitin added supplement. The glucosamine with chondroitin supplement and supply used throughout the study was assessed by the FDA to ensure purity, dosage, quality and consistency. Joint changes were monitored through the study with X-rays. The results stated that glucosamine and chondroitin did not improve joint integrity or subjective pain with any statistical significance and actually equaled the placebo results. The study did indicate that the length of time for dosing was in months, a more long-term study may indicate statistical significance. Other reputable studies done recently had a smaller sample size than this one and often did not use adequate controls such as FDA monitoring of the supplement. I mention the FDA monitoring of this study as an important component as the FDA does NOT regulate supplements of any type.

So, in summary at this time there is no clinical proof that glucosamine and chondroitin can decrease pain and assist in cartilage repair in any joint of the body. There is encouragement in longer-term studies, which are under way. There are also no significant side-effects to taking these supplements, which makes them a safe choice for over the counter use. A typical dosage should be 1200 to 1500 mg daily, in case you decide to try this much-discussed supplement yourself. However, no supplement can take the place of working with your health care provider to eat right, exercise and manage your arthritis in a safe manner tailored to your knees.

As I always say to my patients, “If I could cure arthritis I would have my own private island with a fruity drink and a cabana. Until that time, I can certainly improve where you are at now and teach you how to maintain the best level of function possible.”

Dr. Fox is a Physical Therapist at Boston Sports Medicine