Ask Dr. K: Studies on supplements bring mixed results

So I’m not sure there is a verdict yet in this controversy. In fact, I’m going to argue that the controversy may be misguided: It may not be a question of whether these pills help everyone with osteoarthritis or not.

There’s no doubt that we need good and better treatments for osteoarthritis. I speak as a sufferer who had a hip replaced because osteoarthritis had destroyed it. Living with arthritis can be challenging, as the pain and stiffness make it difficult to perform daily tasks most people take for granted.

Glucosamine and chondroitin are compounds found in healthy cartilage, which is the tough but flexible tissue in our joints. Joints are the places where two (or more) bones meet, but bone doesn’t rub against bone. Instead, in most joints it is the cartilage lining one bone “kissing” the cartilage lining the other.

Osteoarthritis involves the breakdown of normal cartilage. So it makes sense that taking supplements of naturally occurring compounds like glucosamine and chondroitin could help maintain cartilage in people with the condition.

Randomized clinical trials have compared each of these two supplements, alone and in combination, against placebo (dummy) pills in people suffering from osteoarthritis of the hip and knee. An analysis of 10 studies that included nearly 4,000 patients did not find much evidence of reduced pain from glucosamine and chondroitin. Some studies found only a temporary benefit, and only among patients with the most pain. On the other hand, there also was no evidence of side effects from these substances.

And consider this: When a randomized trial does not find that a treatment produces better symptom relief than a placebo pill, that means that the average person in the study got no benefit from the treatment. However, it is possible that some of the people in the study really did benefit.

Over the years, I’ve had patients tell me they have less pain and stiffness when regularly taking these supplements. If they think it helps, I don’t discourage them from taking these pills.

If you’re wondering whether you should take them, the answer is, “It depends.” If you have moderate to severe osteoarthritis pain, it’s reasonable to try the glucosamine-chondroitin combination for two to three months. If you find it eases your pain, it’s reasonable to keep using it. If not, you might as well save your money. As always, if you choose to take these or any other alternative treatments, tell your physician.

One caution: Avoid these supplements if you are allergic to shellfish. Some products use shellfish as a source of glucosamine.

Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.