Updated on 6/20/2005
MSM (methylsulfonylmethane) is hyped as a treatment for arthritis pain as well as for a long list of other ailments - everything from constipation to snoring - but there have been no human studies to prove or disprove any of the claims.
The product was developed by Stanley Jacob, M.D., a surgeon at Oregon Health Sciences University Medical School. Dr. Jacob has been researching MSM as well as DMSO (dimethyl sulfoxide), from which MSM is derived, for decades, but even he concedes that MSM is not a "cure" for arthritis and that no studies have shown that it can stop progression of the disease, or repair or preserve cartilage. He does claim that MSM can relieve pain for as long as you take it, but no studies have been published documenting that it really does ease arthritis pain in humans. (Some studies have shown that it can work in mice.)
As far as safety is concerned, there is no evidence that MSM can be harmful. High doses can cause such adverse effects as diarrhea, stomach upsets or mild cramps. If you take any blood-thinning drugs, you should be aware that MSM can have a blood-thinning effect. I've seen no studies suggesting that MSM can harm the liver. A 2001 study at the Huntington Medical Research Institutes in Pasadena, CA, found that significant concentrations of MSM can cross the blood-brain barrier (the biological shield that protects the brain from toxins and most drugs). The significance of this finding is not clear, and no adverse effects were observed in this study.
Much of the medical skepticism about MSM stems from its relationship to DMSO, which is both a prescription drug (approved only for the treatment of the bladder condition interstitial cystitis) and an industrial solvent. Although DMSO has been widely studied and, in some countries is approved for treatment of arthritis, it is not available here for that use. I recommend topical application of DMSO (from solvent sold in health stores) for treatment of sprains, tendonitis and bursitis, but not for arthritis.
My feeling is that there are many effective treatments for arthritis that are worth trying before resorting to an unproven one. I recommend that everyone with osteoarthritis read "The Arthritis Cure" by Jason Theodosakis, M.D., Brenda Adderly and Barry Fox, PhD. (St. Martin's Press, 1997) and consider using glucosamine sulfate (1,500 mg daily) with or without chondroitin sulfate (1,200 mg daily).
Andrew Weil, M.D.