By presidential proclamation, we're living in the National Bone and Joint Decade, 2002-2011, and that means we should be seeing a surge in research into causes and treatments of arthritis and other diseases.
Meanwhile, many people with osteoarthritis (OA) and rheumatoid arthritis (RA) seek relief by buying the latest book or nutritional supplement claiming to relieve or cure arthritis, or they take advice from a neighbor who swore that eating gin-soaked raisins eased her symptoms.
How do you navigate this gray area of unregulated therapies to know if what you're doing can help or harm? WebMD talked with two experts who provided insight into the claims made for arthritis diets and supplements. Hayes Wilson, MD, is a rheumatologist in Atlanta and medical adviser for the Arthritis Foundation. Christine Gerbstadt, RD, MD, practices in Pittsburgh and is a spokeswoman for the American Dietetic Association.
Here's a guide to help you sort fact from fiction:
- Eliminate nightshades. One of the most common diet claims is that eliminating nightshades, which include potatoes, tomatoes, eggplants, and most peppers, relieves arthritis. This diet probably isn't harmful, but there are no studies to support it.
- Alkaline diet. The alkaline diet presumes both OA and RA are caused by too much acid. Among the foods it excludes are sugar, coffee, red meat, most grains, nuts, and citrus fruits. It's meant to be followed for just one month. It may be that people feel better because they lose weight, reducing stress on joints, which eases pain. There are no studies to support it.
- Dong diet. This restrictive diet relies heavily on vegetables, except tomatoes, and eliminates many of the same foods as the alkaline diet. There's no evidence it affects arthritis.
- Vegetarian diet. Some people report improvement in symptoms, but evidence is mixed. One small study of people with RA showed improvement in four weeks, and follow-up studies of those who stayed on the diet showed continued improvement after one and two years.
- Switching fats. One of the known correlations between food and arthritis is that omega-6 fatty acids increase inflammation, and omega-3 fatty acids reduce it. Limit intake of meat and poultry, and increase your intake of cold-water fish, such as sardines, mackerel, trout, and salmon. For salad dressings and cooking, substitute olive, canola, and flaxseed oils for corn, safflower, and sunflower oils.
- Gin-soaked raisins. Lots of people claim it works, but experts say there's no evidence. Grapes and raisins do contain anti-inflammatory compounds, but not in amounts that would be therapeutic. The gin might dull pain, but drinking to excess sabotages health benefits of nutrients and vitamins, and introduces a whole new set of problems.
- Green tea. Drinking three to four cups of green tea a day could help people with RA. Studies funded by the Arthritis Foundation showed that giving the polyphenolic compounds in green tea to mice significantly decreased the incidence and severity of RA. Human studies have not yet confirmed the results.
- ASU (avocado-soybean unsaponifiable). French studies of ASU, derived from avocado and soybean oils, show it can relieve OA pain, stimulate cartilage repair, and lower a patient's need for nonsteroidal anti-inflammatory drugs (NSAIDs) to control pain. Jason Theodosakis, MD, author of The Arthritis Cure and champion of glucosamine chondroitin, believes ASU will have a major impact on treatment of OA. Sold in France by prescription under the name Piascledine 300, it's available in the U.S. without a prescription.
- Black currant oil. See GLA.
- Borage oil. See GLA.
- Boron. Population studies show that people who have high-boron diets have a very low incidence of arthritis, and there's evidence that people with OA and RA can benefit. The best sources of boron are fresh fruits and vegetables and, depending on where you live, drinking water.
- Bovine cartilage. Taken from the windpipe and trachea of cows, it's supposed to act as an anti-inflammatory agent in the treatment of OA and RA. A few animal and laboratory studies are promising, but there are no human studies to support claims. Researchers also think it may promote regrowth of cartilage.
- Bromelain. This substance found in pineapple is supposed to relieve pain and swelling in OA and RA and improve mobility. There are no studies that show it's effective by itself, but one study of a bromelain supplement containing the enzymes rutin and trypsin relieved pain and improved function in 73 people with knee OA. The effect was similar to taking an NSAID.
- CMO. It's touted as an "arthritis cure," but there's no human clinical evidence to support it.
- Chondroitin sulfate. Used for many years in Europe to relieve OA pain, it's been shown to stop joint degeneration, improve function, and ease pain. One study followed patients with OA in finger joints for three years, and showed fewer patients developed further cartilage damage. It can take two months or more to realize the effects of chondroitin.
- DMSO. Once widely used to relieve joint and tissue inflammation, it fell out of favor when animal studies showed high doses damaged the lens of the eye. Don't use it without consulting your doctor.
- Evening primrose oil. See GLA.
- Fish oil. Studies show it relieves the pain of RA.
- Flaxseed. There are many good nutritional reasons to add it to your diet, but studies of its effect on arthritis have shown mixed results. Its anti-inflammatory properties work best if other vegetable-based oils are restricted.
- GLA. Gamma linolenic acid (GLA) is an omega-6 fatty acid the body uses to make anti-inflammatory agents, unlike other omega-6 fatty acids that actually increase inflammation. It's found in evening primrose oil, black currant oil, and borage oil supplements. Several studies show it relieves the stiffness and pain of RA. In one study, some patients were able to quit taking NSAIDs.
- Ginger. It's known to have painkilling and anti-inflammatory agents. Ginger is believed to reduce joint pain and inflammation in people with OA and RA, and protect the stomach from gastrointestinal effects of NSAIDs. A clinical study showed ginger reduced knee OA pain.
- Glucosamine. As glucosamine hydrochloride or glucosamine sulfate, this supplement relieves symptoms for many, but not all, people with OA. It helps the body build and repair cartilage. In a double-blind study, glucosamine sulfate was as effective in relieving symptoms in patients with knee OA as ibuprofen and had fewer side effects. It takes about two months to realize the effectiveness of this supplement. And it's derived from crab, lobster, or shrimp shells, so check with your doctor before taking any kind of glucosamine if you are allergic to shellfish.
- Glucosamine chondroitin. Many OA patients get relief by taking glucosamine and chondroitin together, but it's not known whether the combination is more effective than taking them alone. That's the subject of a National Institutes of Health (NIH) study called GAIT (glucosamine/chondroitin arthritis intervention trial) now under way. The research shows how effective the supplements are in terms of improving functional ability and reducing pain in people with knee OA. Results are expected to be published in 2005.
- MSM. It's widely touted for relief of pain and inflammation. Its safety and effectiveness have yet to be determined.
- SAM-e. Many European studies over the last 20 years show SAM-e is as effective as anti-inflammatory painkillers in treating OA but with fewer side effects. It works in conjunction with vitamin B-12, B-6, and folate. Claims that SAM-e repairs and rebuilds cartilage lack evidence, as studies have been done only in the lab and in animals.
- Shark cartilage. Ground-up cartilage from Pacific Ocean sharks is supposed to relieve the inflammation and pain of arthritis. Animal and lab studies are promising, but there are no human studies to support claims. Researchers also think it may promote regrowth of cartilage.
- Stinging nettle. Taken orally or applied to the skin, stinging nettle is supposed to reduce the pain and inflammation of OA. Some studies show that patients can lower their dosages of NSAIDs by taking stinging nettle in extract form. Two small studies showed stinging nettle applied topically reduced pain for people with hip OA and thumb joint pain.
- Turmeric. This supplement is used in traditional Chinese and Indian Aruyvedic medicine to relieve pain, stiffness, and inflammation of OA and RA. A small study that combined turmeric, boswellia, and zinc showed decreased pain in OA. Two studies using a combination of turmeric, boswellia, ginger, and aswangandha relieved pain and inflammation in RA. Its effectiveness alone is unknown.
- Wild yam. Although it contains natural anti-inflammatory steroids, it is likely they're not in a form the body can use.
Experimenting with foods and supplements is not without risks. "I know people get desperate enough to try anything, but I would not feel comfortable eliminating whole groups of food," says Gerbstadt. "Before you eliminate any foods or modify your diet, check with a nutritionist."
"The best advice is to eat a healthy, well balanced diet and stay close to your ideal body weight so affected joints have less extra weight to carry around," says Wilson. "Also get plenty of rest and exercise and decrease stress."
Be aware that many supplements interfere with or enhance effects of medications you're already taking. For example, a number of supplements increase the effects of blood-thinning medication. Check with your doctor.