If we can prevent or decrease the pain of arthritis with a relatively inexpensive supplement, why shouldn’t we? Americans spent an estimated $813 million on glucosamine and chondroitin sulfate supplements for ourselves and for our pets in 2012, despite the lack of evidence that it is at all helpful to prevent or alleviate arthritis. Now another study shows that the supplements don’t really help, and may actually do the opposite of what they’re supposed to.

We’ve been discussing this for years. The logic of “well, it can’t hurt” can actually hurt you. Glucosamine and chondroitin supplements have been shown to interfere with some blood-thinning medications. This study, published in the latest issue of the journal Arthritis & Rheumatology, shows something even worse. Bone marrow lesions are thought to worsen arthritis pain, and participants who took the supplements actually had more of them than participants in the control group. Since there were only a few hundred people in the study, this is far from definitive, but it’s not a sign that you should rush out and buy a new bottle of glucosamine, either.

The theory behind taking the supplements makes sense, and some very early studies showed that it worked. They consist of supplements that form the building blocks of cartilage. Therefore, if arthritis is what happens when cartilage deteriorates, putting more of those substances in the body would make cartilage last longer, rebuild it, or … something. The theory was nice, but further studies have showed that the supplements don’t actually help.

Glucosamine Fails to Prevent Deterioration of Knee Cartilage, Decrease Pain [Arthritis & Rheumatology]
One more reason to skip glucosamine for your knee pain [Consumer Reports]

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