MSM (methylsulfonylmethane)

MSM, or methylsulfonylmethane, is an organic sulfur compound present in some foods and synthesised for supplements, marketed to support joint health, often alongside [glucosamine](/glossary/glucosamine) and [chondroitin](/glossary/chondroitin). The sulfur it supplies is presented as useful for cartilage and connective tissue. The level of evidence in dogs and cats is weak: clinical studies specific to companion animals are scarce, and available data do not allow a firm claim of benefit on pain or mobility (veterinary literature). MSM therefore belongs to the category of popular but poorly validated joint supplements, and its presence in a joint formula guarantees no measurable effect. It is generally considered well tolerated at usual doses. Editorial caution requires not presenting MSM as a treatment, but at most as a possible add-on without strong proof, since a true joint problem calls for veterinary assessment and weight management as the priority, with any therapeutic medication prescribed by a vet. The marker: MSM is often added to round out a joint-health story without its own contribution being demonstrated in animals, and the line between marketing argument and clinical data should stay clear. Its evidence gap mirrors that of [turmeric and curcumin](/glossary/turmeric-curcumin), and it is most often reached for in cases of [dysplasia](/glossary/dysplasia) and age-related joint wear covered across the [Petipedia glossary](/glossary).

Petipedia · Editorial team

General documentary information. For an individual animal, a veterinarian's advice takes precedence over any online content.