If you experience joint pain you may be tempted by supplements such as glucosamine and chondroitin, which are often taken together, or omega-3 pills such as fish oil. Last year, U.S. consumers spent some $721 million on glucosamine and chondroitin and some $1.1 billion on fish and other animal oils. Here, we look at the evidence for when these supplements might help—and other pain management strategies to try. 

Omega-3 Supplements

Research suggests that high doses of fish oil, or other sources of omega-3 fatty acids, may help for one particular type of joint pain: rheumatoid arthritis. But its effect on most other types of joint pain, including osteoarthritis, is unclear.

For example, an analysis in the Journal pain that looked at 17 randomized controlled clinical trials found that people with rheumatoid arthritis who took 1.7 to 9.6 grams of fish oil a day reported less joint pain, tenderness, and stiffness. The analysis also found that people who took more than 2.7 g per day reported a greater improvement in morning stiffness and painful or tender joints than those who took lower doses.

But taking fish oil isn’t risk-free. “Even at doses below three grams per day, fish oil can cause side effects, including upset stomach, diarrhea, and a tendency to burp,” says Consumer Reports' chief medical adviser Marvin M. Lipman, M.D. “And the higher the dose you take the more likely you are to experience gastrointestinal problems,” he says.

Another problem: Dietary supplements aren’t regulated by the Food and Drug Administration the same way as medications, so there’s no guarantee that the fish oil listed on the label is in the bottle, that it’s good quality, or that it’s safe to take. According to the American College of Rheumatology, “Some fish oil supplements may contain high levels of mercury or vitamin A, which could be toxic.”

Glucosamine and Chondroitin Supplements

A 2010 trial of 662 people with knee osteoarthritis published in the Annals of the Rheumatic Diseases did find that these supplements relieved pain for some people—but over time they were no more effective than a placebo. And more recently, a study of 1,625 people published in the journal Arthritis & Rheumatology in 2015, found that using glucosamine and chondroitin over a four year period did not relieve knee pain or prevent cartilage loss in people with osteoarthritis any better than a placebo. The American Academy of Orthopaedic Surgeons does not recommend these supplements for osteoarthritis of the knee.

What to Do Instead

One step is to lose weight. Research suggests that every pound of excess weight you shed can take about four pounds of pressure off the knees when walking. Strength training can help build up the muscles that support the affected joint. Gentle, low-impact exercise such as swimming and walking can relieve dull knee pain by keeping the joints flexible and lubricated, Lipman says. For flare-ups, try over-the-counter medications such as ibuprofen (Advil and generic) or naproxen (Aleve and generic)

Editor's note: This article originally appeared in the September issue of Consumer Reports magazine.