MSM

Methylsulfonylmethane is a naturally occurring organosulfur compound found in trace amounts in fruit, vegetables and cow's milk, and industrially produced as a stable oxidation product of dimethyl sulfoxide. Unlike DMSO it has no odour and no skin-penetrating theatrics, which is why it became the practical supplement of the pair.

Its usefulness rests on two mechanisms. MSM donates bioavailable sulfur, a requirement for synthesising glutathione, methionine, cysteine, and the sulfated glycosaminoglycans of cartilage. It also directly downregulates NF-kB signalling and NLRP3 inflammasome activation, reducing IL-6, TNF-alpha and oxidative stress markers.

The clinical evidence is modest but coherent. Randomised trials in knee osteoarthritis at 3-6 g/day for twelve weeks show statistically significant reductions in WOMAC pain and physical function scores, with effect sizes smaller than NSAIDs but with a far better tolerability profile. Combination with glucosamine appears additive. In exercise studies, 3 g/day reduces post-exercise creatine kinase, muscle soreness and markers of oxidative stress, though performance itself is unchanged.

Where MSM is oversold is dermatology and hair. The idea that sulfur content translates to keratin quality is mechanistically plausible and clinically unproven — there is one small trial on facial skin quality and essentially nothing on hair growth. Tolerability is excellent, with mild gastrointestinal upset the main complaint, and doses up to 6 g/day have been used safely for months.