Also, the recent studies that have been in various national newspapers slating Glucosamine are based on major trials using Glucosamine HCL, not Sulphate.
The largest and best-designed clinical trial is the Glucosamine/chondroitin Arthritis Intervention Trial (GAIT), which is funded by the National Institutes of Health. So far, the GAIT has produced two sets of negative results. In 2006, the researchers reported on a 24-week study that involved 1583 patients who were randomly assigned to receive 500 mg of glucosamine hydrochloride three times daily, 400 mg of sodium chondroitin sulfate three times daily, 500 mg of glucosamine plus 400 mg of chondroitin sulfate three times daily, 200 mg of celecoxib (Celebrex) daily, or a placebo. The study found that glucosamine and chondroitin, alone or together, did not reduce osteoarthritis knee pain more effectively than a placebo. The drug group did about 17% better than the placebo group .
[Based on this study], it seems prudent to tell our patients with symptomatic osteoarthritis of the knee that neither glucosamine hydrochloride nor chondroitin sulfate alone has been shown to be more efficacious than placebo for the treatment of knee pain. If patients choose to take dietary supplements to control their symptoms, they should be advised to take glucosamine sulfate rather than glucosamine hydrochloride and, for those with severe pain, that taking chondroitin sulfate with glucosamine sulfate may have an additive effect. Three months of treatment is a sufficient period for the evaluation of efficacy; if there is no clinically significant decrease in symptoms by this time, the supplements should be discontinued. Furthermore, there is no evidence that these agents prevent osteoarthritis in healthy persons or in persons with knee pain but normal radiographs .