MSM (Methylsulfonylmethane)

Medically Reviewed by Melinda Ratini, MS, DO on September 07, 2023
3 min read

MSM is a chemical in animals, humans, and many plants. People use it most often to try to treat arthritis.

MSM can be produced in a lab, where it is sometimes combined with other supplements such as glucosamine or chondroitin.

People take MSM by mouth or apply it to the skin, mostly using it to lessen inflammation.

They take MSM to try to relieve pain or swelling from:

People also apply MSM to the skin to try to treat problems such as:

Or they may take it to try to treat gastrointestinal problems such as:

There is a whole range of other reasons people take MSM. This includes obesity and liver problems, high blood pressure, high cholesterol, gum disease, snoring, infections, lung problems, Alzheimer's, HIV, and cancer.

The evidence to support taking MSM for these is lacking.

However, there is evidence that MSM in combination with other supplements may help a bit with the pain and swelling of knee osteoarthritis. Also, early animal research shows some promise for decreasing joint degeneration.

Limited small studies also show that MSM may help with exercise recovery. But researchers have more work to do to confirm this.

MSM has shown some effectiveness for treating allergies, repetitive stress injuries, certain bladder disorders like interstitial cystitis, and wounds, but more research is needed before it can be recommended for any of these conditions.

People have tried taking from 500 milligrams of MSM twice daily to 3 grams once daily for osteoarthritis. However, optimal doses of MSM have not been set for any condition. And quality and active ingredients in supplements may vary widely from maker to maker. This makes it hard to set a standard dose.

Very small amounts of MSM can be found in:

  • Fruit
  • Corn
  • Tomatoes
  • Tea and coffee
  • Milk

But the amounts in these foods are a small fraction of the amount in supplements.

Chances are it is safe if you take up to 6 grams of MSM by mouth for six months or fewer.

Side effects. There isn't enough information about MSM's safety when you apply it to the skin.

So far, studies have shown minimal side effects when MSM is taken orally in a dosage of 3 grams daily for six months, but some people may experience mild gastrointestinal side effects such as discomfort or diarrhea.

Risks. Don't take any chances if you are pregnant or breastfeeding. Doctors don't know enough about the safety of MSM in these circumstances. So it's best not to take it. Don't take any chances if you are pregnant or breastfeeding. Doctors don't know enough about the safety of MSM in these circumstances. So, it's best not to take it. 

Interactions. There doesn't appear to be an interaction between MSM and medications, herbs, supplements, or foods.

The FDA does not regulate supplements with the same stringency as they do food and medicine. Unlike drug manufacturers, makers are responsible for the safety and labeling of their own products.

Be sure to tell your doctor about any supplements you’re taking, even if they’re natural. That way, they can check on any potential side effects or interactions with medications, foods, or other herbs and supplements.