A mounting body of research suggests certain common supplements may have help relieve pain and increase range of motion in people with osteoarthritis (OA) of the knee. These easy-to-find supplements include fish oil and glucosamine.

Before buying supplements for your OA, keep in mind that they aren’t regulated by the U.S. Food and Drug Administration (FDA). Despite label and marketing claims, supplements don’t undergo the rigorous manufacturing and regulatory processes of prescription drugs. Supplements are prone to wide fluctuations in consistency from batch to batch, or even pill to pill.

This lack of regulation has made it difficult to study the possible benefits of nutritional supplements. It’s also contributed to the inconclusive results of many clinical trials.

Still, the naturally occurring chemicals in certain dietary supplements may have an effect on the body’s inflammatory mechanisms. Inflammation is the body’s natural way of protecting itself. It helps to fight infections, increase blood flow to areas that need healing, and generate pain signals. But these same inflammatory chemicals can also contribute to OA. Chronic inflammation is the result of an out-of-balance immune system.

Read on to learn about some widely available supplements that may benefit people with OA.

The nutritional supplements curcumin and resveratrol have a variety of anti-inflammatory actions. Curcumin is found in turmeric. Sources of resveratrol include grapes, wine, berries, peanuts, and chocolate.

Turmeric, and thus curcumin, has been used in traditional Hindu medicine for at least a thousand years for various ailments, including joint disorders and arthritis. However, only in the past 20 to 30 years has resveratrol been studied in laboratories and in humans for its effects on inflammation and arthritis. These studies have been promising and the mechanism of action seems to be at the bone and cartilage targeted by the immune system’s osteoblast cells.

Omega-3 fatty acids also lead to a spectrum of anti-inflammatory activities. These activities appear to account for much of their beneficial effects on the heart. Studies have shown that people with rheumatoid arthritis who consumed large doses of DHA and EPA omega-3 fatty acids were able to cut back on their use of nonsteroidal anti-inflammatory drugs (NSAIDs). In these studies, people typically consumed upwards of 2 to 4 grams of the fatty acids daily. There is real risk when taking very high levels of omega-3s. Stay within the recommended guidelines.

The American diet is often weak in anti-inflammatory omega-3 fatty acids and high in pro-inflammatory omega-6 fatty acids. If you have OA, you may also benefit from these dietary changes:

  • Eat more cold-water and fatty fish, such as tuna, sardines, and salmon.
  • Choose canola and olive oils over corn oils, coconut oils, and the foods processed with them.
  • Eat foods rich in anti-inflammatory ALA, a major plant source of omega-3s, such as soybeans, flaxseed, pumpkin seeds, walnuts, and tofu.

Read more: Maintaining fitness with osteoarthritis of the knee »

Most herbal medications do not work quickly and glucosamine effects are usually not seen before six months of use. Beneficial effects include in reducing pain, stiffness, limited movement, and swelling. In spite of its popularity, glucosamine has shown inconsistent results in trials of people with OA. Glucosamine is necessary for health and maintenance of cartilage and other joint structures. It has anti-inflammatory properties when taken as a dietary supplement. It also affects the integrity of joint cartilage. According to the Arthritis Foundation, some studies indicate glucosamine may interfere with and slow the progression of OA.

Boswellia serrata (frankincense) is an ancient Indian herb. Herbalists use it as a treatment for arthritis. Boswellia serrata also decreases inflammation and promotes joint health. Its extracts promote natural anti-inflammatory activity where chronic inflammation is present. They switch off the pro-inflammatory cytokines and mediators that initiate the process. This helps manage osteoarthritis and reduces further damage.

Harpagophytum procumbens is also known as devil’s claw or grapple plant. Devil’s claw seems to help decrease OA-related pain, whether taken alone or with NSAIDs. A 2000 study found that, after four months of treatment, the herb works nearly well as the OA drug diacerein to improve hip and knee pain. Diacerein is a slow-acting drug that’s unavailable in the United States. This study used Harpadol, a powdered devil’s claw root product. At the end of the study, some participants were able to lower their doses of NSAIDs and antalgic (pain-reducing) drugs. This herb seems to interact with interleukins, another chemical in the cascade of inflammation.

Supplements can be a part of your OA treatment plan. But you should always check with your doctor or pharmacist first before starting any supplements. There may be unintended side effects if you’re already taking other medications.

Learn more: Osteoarthritis medications »