Methylsulfonylmethane (MSM) is a naturally occurring compound in foods such as fresh vegetables, meat, and dairy products. MSM provides a source of natural sulfur. MSM may be beneficial for joint pain, skin inflammation, and other conditions.

Typically, MSM supplements contain a synthetic form of MSM. The primary uses for MSM supplements include arthritis, joint pain, muscle recovery after exercise, and allergy relief.

Many of MSM’s benefits have links to its anti-inflammatory action. Inflammation is a factor in many health conditions, including arthritis, allergies, and skin conditions. By reducing inflammation, MSM may be able to reduce or eliminate certain symptoms.

According to research findings, MSM could be useful for treating several different medical conditions. The following are some of the best-documented uses for MSM in medical studies.

Osteoarthritis, which affects around 32.5 million people in the United States, is a deterioration of the cartilage in one or more of the joints. It commonly affects the knees, hips, lower back, hands, and fingers. It can cause pain, stiffness, and swelling.

Various studies suggest that taking MSM supplements could help with symptoms of arthritis or relieve joint pain.

A study of 100 adults over 50 years of age took either an MSM supplement or a placebo. The MSM supplement also had vitamin C, collagen, and neem and corydalis extracts. The results show people who took the MSM supplement for 12 weeks experienced improvements in joint pain, stiffness, and swelling compared with those taking placebo medication.

Another double-blind study featured 100 adult participants who had hip or knee osteoarthritis. They took MSM supplements and reported improvement in their arthritis symptoms and better performance in daily activities than those who took a placebo. The MSM dosage was 6 grams (g) per day for 26 weeks.

While it is popular as a natural arthritis treatment, MSM may not work for everyone. The Arthritis Foundation states that there are currently no large, well-controlled studies on MSM.

A 2018 meta-analysis found that MSM may improve osteoarthritis symptoms in the short term, but its importance clinically was not clear.

Regular exercise is necessary for good health. However, the energy demands of exercise can cause oxidative stress to muscles and tissues. This may result in temporary soreness and discomfort after a workout.

MSM supplements may help improve post-workout pain and tissue stress. Some small studies suggest that it could be helpful for this, including:

  • A study of 16 untrained healthy males, which suggests that taking an MSM supplement helps reduce biomarkers of oxidative stress after exercise. It also increased the total antioxidant capacity of their blood.
  • Another study of 22 healthy people who received 3 g of MSM or a placebo per day for 3 weeks leading up to a half marathon. It suggested that those who took MSM reported less muscle soreness and joint pain compared to those who took a placebo.
  • A study on 24 exercise-trained males found that those who took 3 g of MSM daily for 14 days had less pain and discomfort after exercise than those taking a placebo.

It is important to note that none of the studies looked at a large group of participants.

Nasal allergies, or allergic rhinitis, are an immune system response to something ordinarily harmless. Nasal allergies can cause sneezing, itching, watery eyes, and coughing when a person has exposure to an allergen, such as pollen, dust, animal dander, or mold.

In a double-blind study, people who took a daily dose of 3 g of MSM had reductions of more than 50% in their allergy symptoms.

People may also use MSM topically by applying it to the skin. Some people believe that the anti-inflammatory power of MSM can help specific skin conditions when applied as a cream.

One double-blind study on rosacea from 2008 found that people with the condition experienced an improvement in their symptoms after using MSM cream. The cream also contained silymarin or milk thistle. However, no larger or more recent studies have compounded these findings, so there is not enough evidence to support the effect of MSM in this area.

Despite the lack of medical studies, MSM is a natural source of sulfur, which could be beneficial to the skin. Dermatologists have long prescribed sulfur creams and washes to treat skin conditions, including rosacea and acne. Topical sulfur has natural antibacterial and anti-inflammatory properties.

According to the Food and Drug Administration (FDA), MSM is considered safe at dosages under 4,000 milligrams (mg) per kilogram (kg) per day and in energy bars at levels up to 30,000 mg/kg. MSM supplements are available in capsule or powder form.

Taking more MSM than directed does not appear to provide better results. In the 2018 allergy study, people taking 12 g of MSM had less allergy relief than those taking 3 g.

People may also apply a cream that contains MSM to the skin. They should look for a product that specifies how much MSM it contains and how often to apply it.

People who are already using prescription creams for rosacea or other skin conditions should ask their dermatologist before trying MSM cream.

Taking excessive amounts of MSM could have unwanted and potentially dangerous effects. A 2013 study on rats found that those receiving typical human dosages saw an improvement in the health of knee cartilage.

However, when the researchers gave the rats 100 times the standard human dose, they experienced shrinkage of several organs, including the liver and spleen.

The Arthritis Foundation advises people who take blood thinners to avoid MSM. They also report that MSM could cause an upset stomach or diarrhea.

Most people can take the usual range of 3 g per day of capsules, powder, or cream without serious side effects, but people should speak with a doctor before taking the supplement long-term. One study suggests that MSM levels in the body may build up over time.

MSM is not sulfur in itself. However, it is an organic compound that contains sulfur. This is the same sulfur that exists naturally in the body, as well as in vegetables, fruits, grains, and meats.

For this reason, MSM is also known as dimethyl sulfone and methyl sulfone. A person can get MSM naturally from food, but producers can also make the compound synthetically by combining dimethylsulfoxide and hydrogen peroxide.

Some small studies show that MSM may be useful for treating several different medical conditions. It is typically safe when people take it at normal dosages of around 3 g per day.

MSM may be worth trying for those looking for a natural alternative for arthritis pain, post-exercise soreness, seasonal allergies, or rosacea.

Pregnant or breastfeeding people, children, and people who have health conditions should speak with a doctor before taking MSM. It may not be safe or recommended for these people.