Some research has just been released that Glucosomine and Chondroitin Sulfate does help repair minor cartilage defects. The study was done on horses. They stated that although it could never be determined if it would prevent osteoarthritis, the efficiency of repair of minor arthritis defects led them to conclude that Glucosomine and chondroitin could be beneficial in the prevention or delaying the onset of osteoarthritis.
The Horse | Chondroitin Sulfate, Glucosamine's Effects on Equine OA
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Link works, thanks!