MSM supplement: what it is and whether it helps joints
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- Pure MSM powder. Best for: People who want gram doses without many capsules. See options on Amazon
- MSM 1,000 mg capsules. Best for: People who prefer capsules. See options on Amazon
- Glucosamine chondroitin MSM. Best for: People with knee osteoarthritis who want the combination studied in a 2024 meta-analysis. See options on Amazon
What MSM is
Methylsulfonylmethane (MSM) is a naturally occurring organic sulfur compound, also called dimethyl sulfone or methyl sulfone. A 2017 review in Nutrients explains that it is related to dimethyl sulfoxide (DMSO), which was widely studied from the 1950s to 1970s, and researchers began testing odorless MSM in the late 1970s looking for similar uses.
One MSM product received Generally Recognized As Safe (GRAS) status from the FDA in 2007. The review notes that in a study of 20 healthy men, taking 3 g a day for four weeks raised MSM levels in the blood, showing it is absorbed.
What the research shows
| Use | Evidence summary |
|---|---|
| Osteoarthritis pain | Trials suggest less pain; dose still being refined |
| Glucosamine, chondroitin and MSM combo | Reduced knee pain in a 2024 network meta-analysis; low-quality evidence |
| Exercise muscle soreness | Reduced in some studies |
| Seasonal allergies | One 30-day study at 2.6 g a day |
Joint pain. The 2017 review reports clinical trials in which MSM lowered pain on standard osteoarthritis scales. It also notes that a glucosamine, chondroitin and MSM combination gave only marginal improvement when added to diet and exercise changes in sedentary obese women with osteoarthritis.
Combinations for knee pain. A 2024 network meta-analysis in the Journal of Clinical Medicine (30 trials, 5,265 patients) found glucosamine plus chondroitin plus MSM reduced knee osteoarthritis pain compared with placebo, but rated that evidence low quality.
Exercise. The review describes studies where MSM reduced markers of exercise muscle damage and muscle soreness.
Keep in mind that one author of the 2017 review worked for an MSM maker and another consulted for supplement companies, including MSM sellers.
Safety
- Generally well tolerated. The review says most people tolerate up to 4 grams a day with few known, mild side effects. Under the FDA GRAS notice, MSM was considered safe below about 4,845.6 mg a day.
- Gas. NOW Foods advises reducing the dose if intestinal gas occurs.
- Glaucoma. NOW Foods' label specifically says to consult a physician if you have a medical condition, especially glaucoma.
- Alcohol. The review notes online anecdotes about alcohol sensitivity with MSM and says no studies have examined it; more research is needed.
- Pregnancy and medicines. NOW Foods lists MSM for adults only and advises a physician check if pregnant, nursing or taking medication.
- Skin and eyes. The review notes technical reports of mild skin and eye irritation when MSM is applied topically.
MSM powder vs capsules
- Powder. NOW Foods' MSM Powder gives 1.8 g (1,800 mg) per half teaspoon, taken 1 to 2 times daily in juice or another liquid, with no other ingredients.
- Capsules and tablets. NOW Foods sells 1,000 mg capsules, and other brands sell tablets. You may need several to reach doses used in studies.
- Combination joint formulas. Many products mix MSM with glucosamine and chondroitin. See our glucosamine chondroitin guide for that evidence and its shellfish and warfarin cautions.
How to choose an MSM supplement
- MSM mg per serving. Compare to amounts in the research, such as 3 g a day in the absorption study and 2.6 g in the allergy study.
- Stay within studied limits. Most people tolerated up to 4 g a day in the review.
- Single ingredient. If you want MSM itself, choose a product whose only ingredient is MSM.
- Start low. Begin with the smallest label serving and adjust if gas or stomach upset occurs.
- See a doctor for ongoing joint pain to confirm the cause.
What to look for when you buy
Pure MSM powder
Best for: People who want gram doses without many capsules
NOW Foods' MSM Powder lists 1,800 mg per half teaspoon with no other ingredients.
Watch out: Mix in juice or another liquid. Reduce the dose if gas occurs. Ask a doctor first if you have glaucoma.
See options on AmazonMSM 1,000 mg capsules
Best for: People who prefer capsules
NOW Foods sells MSM in 1,000 mg capsules.
Watch out: Several capsules may be needed to match studied amounts.
See options on AmazonGlucosamine chondroitin MSM
Best for: People with knee osteoarthritis who want the combination studied in a 2024 meta-analysis
The combination reduced knee pain versus placebo in the 2024 analysis, though evidence was low quality.
Watch out: Often contains shellfish. Glucosamine and chondroitin can raise bleeding risk with warfarin.
See options on AmazonQuestions people ask
- What is MSM supplement good for?
- It is mainly used for joint pain. Trials suggest it may reduce osteoarthritis pain and exercise soreness, but the best dose is still being studied.
- How much MSM should I take?
- Follow the label. The review says most people tolerate up to 4 g a day. NOW Foods' powder serving is 1.8 g, 1 to 2 times daily.
- What are MSM side effects?
- Side effects are few and mild. NOW Foods notes intestinal gas and advises a lower dose if it occurs.
- Can I take MSM with glaucoma?
- Ask your doctor first. NOW Foods specifically flags glaucoma on its MSM label.
- Is MSM the same as sulfur?
- MSM is an organic sulfur compound. The 2017 review notes it is sold under names including organic sulfur, but it is a specific compound.
Sources
- Methylsulfonylmethane: Applications and Safety of a Novel Dietary Supplement (pmc.ncbi.nlm.nih.gov), Nutrients (PMC5372953)
- Comparative Efficacy of Glucosamine-Based Combination Therapies in Alleviating Knee Osteoarthritis Pain: A Systematic Review and Network Meta-Analysis (pmc.ncbi.nlm.nih.gov), Journal of Clinical Medicine (PMC11641979)
- MSM Powder (www.nowfoods.com/products/supplements/msm-powder), NOW Foods