Methylsulfonylmethane (MSM) is an organosulfur compound commonly used as a dietary supplement for joint health. Its use is primarily supported by scientific evidence, though the body of research is moderate and not unequivocal. Several randomized, double-blind, placebo-controlled trials have investigated MSM’s effects on joint pain and function, particularly in individuals with osteoarthritis. For example, a 2006 study published in Osteoarthritis and Cartilage found that MSM supplementation (3g twice daily) for 12 weeks led to significant improvements in pain and physical function compared to placebo in patients with knee osteoarthritis. Other studies have reported reductions in swelling and improved mobility, though the magnitude of benefit varies and some trials report only modest effects.

The proposed mechanisms include MSM’s anti-inflammatory and antioxidant properties, which may help reduce joint degeneration and discomfort. MSM is thought to inhibit the release of inflammatory cytokines and reduce oxidative stress in joint tissues. While these findings are promising, systematic reviews and meta-analyses generally conclude that, although MSM appears safe and may provide benefit for some individuals, the evidence base is limited by small sample sizes, short durations, and potential publication bias. Further large-scale, long-term studies are needed to confirm its efficacy and clarify its role among joint health interventions.

In summary, MSM is scientifically investigated and shows some potential for supporting joint health, but the strength of the evidence is moderate rather than strong.