If you’re one of the more than 30 million Americans with osteoarthritis, or OA, the most common form of arthritis, you’ve probably thought about treatments other than medication to ease pain. About 40 percent of those with arthritis have tried a complementary or alternative therapy such as acupuncture or yoga, according to the Centers for Disease Control and Prevention.

“When conventional medicine fails to relieve arthritic pain, many sufferers turn to alternative methods,” says Marvin M. Lipman, Consumer Reports’ chief medical adviser. “But not only is there little evidence to support many of those treatments, some aren’t even regulated.”

Are any useful? “These are not game-changers,” says Richard Panush, a professor at the Keck School of Medicine at the University of Southern California. “Some, at best, may have small effects in some circumstances for some people.”

Treatments that may help

Massage. A review of studies published in Mayo Clinic Proceedings suggests that massage therapy can ease the pain and stiffness of knee OA. Researchers in one study recommended a weekly 60-minute session with a licensed massage therapist. (Find one at amtamassage.org.)

Tai chi. The Chinese exercise, with its slow, rhythmic movements, was shown in a 2015 review of 54 studies to cut arthritis pain slightly. But it was less effective than aerobic and strength exercises. (Get more info at ­americantaichi.org.)

Yoga. A review of 17 studies published in the journal Musculoskeletal Care found that yoga reduced OA pain. Consumer Reports’ experts recommend avoiding Bikram (hot yoga) if you have joint problems. The heat may make you feel as if you can stretch more than you should, which can further damage joints.

Acupuncture. Research suggests that this traditional Chinese therapy, which involves inserting thin needles into the body at particular spots, reduces OA discomfort for some people. One theory is that it may trigger the release of pain-suppressing hormones called endorphins. Or it may simply provide a placebo effect, helping you feel better without a medical reason. Make sure you’re treated by a credentialed practitioner. (Find one at mx.nccaom.­org/findapractitioner.aspx.)

Therapies to avoid

Chiropractic manipulation. Some research suggests that the “realigning” of the spine by a chiropractor can ease some general back and neck pain. But a 2012 review published in the journal Rheumatology found no good evidence that the therapy effectively reduces OA pain.

Dietary supplements. Some people use supplements such as glucosamine and chondroitin (often together) or fish oil for joint pain. So far, studies have shown that glucosamine and chondroitin are no more effective than a placebo. High doses of fish oil may ease the joint ache of rheumatoid arthritis, an autoimmune condition. But its effect on OA is unclear. In addition, fish-oil supplements can cause side effects such as diarrhea and stomach pain. And dietary supplements aren’t well regulated by the Food and Drug Administration, so you can’t be sure the one you take contains what’s on the label.

Homeopathy. The principle behind homeopathy is that certain highly diluted substances can cure illness. For instance, rhus toxicodendron — made from poison ivy — is touted as an OA treatment. But Lipman says there’s no good evidence to support using homeopathic remedies for arthritis or any other condition.

Three smart strategies

Lose weight if you need to. Work on shedding extra pounds. Excess weight puts added pressure on ankles, hips and knees, which can increase arthritis severity and pain.

Get the right kind of exercise. Activities that strengthen muscles, improve your range of motion and boost your cardiovascular activity can help. In addition to tai chi and possibly yoga, consider a regular walking or swimming program. Get more information on arthritis-friendly exercise at arthritis.org/living-with-arthritis/exercise.

Talk with your doctor. If you decide to try an alternative therapy, it’s wise to let your doctor know beforehand. He or she may be able to refer you to a trustworthy practitioner. Your doctor can also tell you about any potential dangers or whether interactions might occur with your regular medication.

Copyright 2017. Consumers Union of United States Inc.

For further guidance, go to ConsumerReports.org/Health, where more detailed information, including CR’s ratings of prescription drugs, treatments, hospitals and healthy-living products, is available to subscribers.