Can glucosamine and chondroitin help people with arthritis?
By Nick Gallo
Can a nutritional supplement available at health food stores and over the Internet battle the pain and symptoms of osteoarthritis? Thanks to positive reports from patients and a second look at early studies, some mainstream doctors and researchers are beginning to think the idea has merit.
The supplement consists of glucosamine (glue-COSE-uh-mean) sulfate and chondroitin (con-DROY-tin) sulfate, which are synthetic versions of compounds made by the body to help form cartilage. In osteoarthritis, a wear-and-tear condition that affects 16 million Americans, spongy cartilage that cushions the ends of bone joints breaks down, causing pain, stiffness, and deformity.
Traditionally, physicians treat osteoarthritis with prudent exercise, muscle-strengthening, and anti-inflammatory drugs (aspirin and ibuprofen) to ease the pain. However, these drugs can cause serious side effects, such as gastrointestinal bleeding, and do not slow progression of arthritis.
Naturally produced glucosamine and chondroitin stimulate cartilage growth. Chondroitin also may block an enzyme that destroys cartilage. The notion that supplements might have benefit dates back to the early 1980s when a handful of European studies showed that glucosamine reduced joint pain and swelling. Other studies indicated chondroitin delivered similar relief.
The clinical trials were short-term, but should have attracted interest for follow-up study, except for one problem. The substances were not patentable, discouraging expensive research.
Over the years, veterinarians had good results using the glucosamine/chondroitin combination in dogs and other animals. Then, two years ago, the supplement zoomed into the spotlight when Dr. Jason Theodosakis, a sports medicine specialist at the University of Arizona, promoted use of the supplement in his best-selling "The Arthritis Cure." Since then, millions of arthritis sufferers have tried the supplement, producing enough anecdotal reports of success to prompt interest from experts.
After a recent review of the evidence, Roland Moskowitz, a rheumatologist and professor of medicine at Case Western Reserve University in Cleveland concludes that the glucosamine/chondroitin remedy holds promise. "The studies were limited, but they were reasonably well done," he says. "There was enough smoke there to say this is worth investigating."
Several researchers at the American Academy of Orthopedic Surgeons have reported that there is enough evidence to recommend the use of glucosamine as an alternative to anti-inflammatory drugs.
Dr. Moskowitz won't go that far. "Basically, if my patients tell me they're taking it, I don't deter them," he explains. "I say, 'Try it for six months and see if you get a response."
If that's not a ringing endorsement, there's reason to be cautious. Experts argue over how and why the product might work. While some believe the combination helps re-grow cartilage and reverse arthritis, others suspect it acts primarily as a pain-reliever or anti-inflammatory drug. In addition, most studies have evaluated glucosamine or chondroitin independently while nutritional supplements typically bundle them together. In theory, the two should complement each other but it hasn't been proven.
Sold as a nutritional supplement and not a drug, glucosamine/chondroitin products are not approved by the Food and Drug Administration. They appear to be relatively safe, but no long-term safety tests have been done. Product quality and potency are not well-controlled, either. In tests, some products have been found to contain much smaller amounts of active ingredients than listed on the label.
The National Institutes of Health now is launching a major study to answer many of these questions. Until its results are in, if you're consider using the supplement, follow this advice from the Arthritis Foundation: Let your doctor know that you are using the supplement. A physician can monitor your progress and be alert for allergies and potentially harmful interactions. Chondroitin supplements may be dangerous if you are taking blood-thinning medications or daily aspirin. Diabetics may need to take special precautions.
Don't take the supplement if you're pregnant or give it to children. The product hasn't been tested in those groups. Don't stop or decrease prescribed medications without consulting your doctor.