In an analysis of -placebo-controlled studies published or performed between 1980 and 2002, the Archives of Internal Medicine reported that those who took oral chondroitin or glucosamine had significantly less knee pain, more range-of-motion, increased walking distance and improved activities of daily life without side effects. Those who took oral glucosamine had less narrowing of the space between the joints, suggesting that glucosamine protects the cartilage which cushions joints. Two reviewers analyzed the data independently of one another, using a conservative approach to determine benefit and did not know the sources or authors of the studies.
In a study of oral glucosamine and MSM in the Journal of Clinical Drug Investigation, researchers recruited 118 men and women with mild to moderate OA. For 12 weeks participants took 500 mg of glucosamine three times per day, 500 mg of MSM three times per day, combined these two treatments or took a placebo. Scientists measured participants at the start of the study and every two weeks and found that glucosamine and MSM, separately and combined, significantly reduced inflammation and pain compared to placebo. Those who took glucosamine and MSM together reported the greatest decrease in pain, had the most rapid relief from inflammation, and the quickest improvement in movement.
In a study of 50 men and women aged 40 to 76 with OA of the knee, participants took a placebo or 3 grams of MSM twice per day. After 12 weeks, the MSM group reported significant decreases in pain and improvements in performing daily functions compared to placebo.
In a 16 week study of 61 adults with OA of the knee in Musculoskeletal Disorders, participants took 1,200 mg of SAMe per day, 200 mg of the prescription drug celecoxib (Celebrex) per day or a placebo and reported that after two months, SAMe reduced pain as effectively as Celebrex.