MSM (Methylsulfonylmethane) After 40
After 40, many active people notice that joints take longer to settle after a hard session and that minor aches linger. Methylsulfonylmethane, or MSM, is often suggested as a gentle helper. It is cheap, widely available and generally well tolerated. Our editors examine whether the evidence justifies taking it in midlife and beyond.
What MSM is
MSM is an organic sulphur compound found in small amounts in some fruits, vegetables, grains, milk and coffee. Commercial MSM is produced synthetically and sold as powder, capsules or tablets, often in combination with glucosamine and chondroitin.
Sulphur is part of the amino acids methionine and cysteine and of glutathione, a key antioxidant. It also contributes to connective tissue molecules. The theory behind MSM supplementation is that it provides bioavailable sulphur and may have anti-inflammatory and antioxidant effects.
A review by Butawan, Benjamin and Bloomer summarised MSM's proposed mechanisms, including effects on inflammatory signalling pathways and on oxidative stress. Most mechanistic data come from cell and animal studies.
In the UK, MSM is sold as a food supplement. There are no authorised health claims for MSM on the GB nutrition and health claims register, so products cannot legally claim to treat or prevent joint disease.
Joints and osteoarthritis: the clinical trials
The age group most often studied is middle-aged and older adults with knee osteoarthritis, which makes the evidence fairly relevant to people over 40.
A pilot trial by Kim and colleagues gave 3 g of MSM twice daily or placebo to adults with knee osteoarthritis for 12 weeks. Pain and physical function scores improved more with MSM, though the changes were modest and the sample small.
Debbi and colleagues conducted a similar randomised trial using 1.125 g three times daily for 12 weeks. MSM produced small improvements in pain and function scores compared with placebo, which the authors judged to be of uncertain clinical significance.
These results are encouraging but limited: few participants, short durations and no evidence of structural cartilage protection. NICE does not recommend MSM for osteoarthritis, and exercise remains the core treatment.
| Study | Participants | Daily intake | Duration | Main finding |
|---|---|---|---|---|
| Kim et al., 2006 | Adults with knee OA | 6 g | 12 weeks | Improved pain and function vs placebo |
| Debbi et al., 2011 | Adults with knee OA | 3.375 g | 12 weeks | Small improvements in pain and function |
| Kalman et al., 2012 | Healthy men | 1.5–3 g | 28 days | Some effects on recovery markers |
| Withee et al., 2017 | Half-marathon runners | 3 g | 21 days | Possible reduction in post-race pain |
Exercise recovery and oxidative stress
Several small studies have looked at MSM in healthy people undergoing strenuous exercise. Kalman and colleagues found changes in markers of oxidative capacity and some indications of improved recovery in men given MSM for 28 days.
Withee and colleagues gave MSM or placebo to healthy adults for three weeks before a half-marathon. The MSM group reported less muscle and joint pain after the race in some measures, although many biochemical markers were similar between groups.
For people over 40, recovery is often a bigger limitation than raw performance. A supplement that marginally reduced post-exercise soreness could be useful, but current studies are too small and inconsistent to be sure.
MSM is not a substitute for the fundamentals that matter most in midlife training: progressive strength work, adequate protein, sleep, sensible weekly load and attention to warm-ups.
Safety and who should be careful
MSM appears to be well tolerated. The Butawan review noted that the US Food and Drug Administration granted it "generally recognised as safe" status for certain food uses, and that adverse effects in trials were mild and uncommon.
We often recommend Steroids UK.
Reported side effects include stomach upset, bloating, diarrhoea, headache and occasionally difficulty sleeping. Taking MSM with meals and starting with a lower amount can reduce digestive symptoms.
Groups who should seek advice before using MSM include:
- pregnant or breastfeeding women, owing to a lack of safety data;
- people taking anticoagulants, as interactions have not been well studied;
- people with significant kidney or liver disease;
- anyone with known sensitivity to sulphur-containing supplements.
Combination products deserve attention. Many contain glucosamine, which interacts with warfarin, or herbal ingredients such as turmeric and boswellia, which have their own interaction profiles. Always read the full label.
How to use MSM sensibly after 40
If you decide to try MSM, trials have used daily amounts from about 1.5 g to 6 g, usually split into two or three servings. A cautious approach is to start at the lower end and increase only if well tolerated.
Give it a defined trial period of about 8–12 weeks and keep notes on joint pain, stiffness and recovery. If there is no clear improvement by then, the supplement is unlikely to be worth continuing.
Choose products from reputable manufacturers that provide batch testing information. MSM is inexpensive, so very cheap products do not necessarily signal poor quality, but transparency about purity is still valuable.
Persistent joint pain, swelling or night pain after 40 should be assessed by a GP or physiotherapist. Conditions such as inflammatory arthritis, gout or degenerative tears require specific diagnosis and management.
Conclusions of the editorial team
MSM is a low-cost, generally well-tolerated supplement with modest evidence for small improvements in knee osteoarthritis pain and possibly in post-exercise soreness.
The trials are small and short, and there is no proof that MSM protects cartilage structure or prevents joint disease.
For people over 40, it can be a reasonable time-limited experiment, but training quality, strength work and recovery habits matter far more. Related topics worth reading include who should avoid glucosamine and chondroitin, collagen for tendons, and anti-inflammatory nutrition for older athletes.
References
- Kim LS, Axelrod LJ, Howard P, et al. Efficacy of methylsulfonylmethane (MSM) in osteoarthritis pain of the knee: a pilot clinical trial. Osteoarthritis Cartilage. 2006;14(3):286–294.
- Debbi EM, Agar G, Fichman G, et al. Efficacy of methylsulfonylmethane supplementation on osteoarthritis of the knee: a randomized controlled study. BMC Complement Altern Med. 2011;11:50.
- Butawan M, Benjamin RL, Bloomer RJ. Methylsulfonylmethane: applications and safety of a novel dietary supplement. Nutrients. 2017;9(3):290.
- Kalman DS, Feldman S, Scheinberg AR, et al. Influence of methylsulfonylmethane on markers of exercise recovery and performance in healthy men: a pilot study. J Int Soc Sports Nutr. 2012;9(1):46.
- Withee ED, Tippens KM, Dehen R, et al. Effects of methylsulfonylmethane (MSM) on exercise-induced oxidative stress, muscle damage, and pain following a half-marathon: a double-blind, randomized, placebo-controlled trial. J Int Soc Sports Nutr. 2017;14:24.
