TUESDAY, Sept. 30 (HealthDay News) -- The popular supplements glucosamine and chondroitin are no better than a placebo at preventing cartilage loss in knees of people with the form of arthritis caused by wear and tear, a new study found.
Still, the researcher who led the study said glucosamine may help some people with osteoarthritis.
The researcher, Dr. Allen D. Sawitzke, an associate professor of internal medicine at the University of Utah School of Medicine, also acknowledged that the trial wasn't conclusive because of the small number of participants and the relatively short duration -- two years.
Sawitzke said that what struck him as possibly significant was the lower rate of joint loss for participants taking only glucosamine -- 0.013 millimeters, about one-tenth as much as found in those taking either other supplements or a placebo.
"That is not statistically significant, but it hints to me that there might be something going on," he said.
"It was a null study that didn't show a difference," Sawitzke admitted, before adding: "That's not the same as saying there is no difference. The result was influenced by the slow rate of progression for everybody. The study actually says more about what we need to do for the next investigation than for what patients should do."
The new findings, published in the October issue of the journal Arthritis & Rheumatism,, was a continuation of the earlier Glucosamine/chondroitin Arthritis Intervention Trial (GAIT), led by University of Utah researchers.
Arthritis sufferers take glucosamine either to reduce pain or to slow progression of the condition, Sawitzke said. "Controls pain -- this study says nothing about it," he said. "Slows progression -- the study says we weren't able to show that."
For the new study, GAIT participants were given the chance to continue their original study treatment for an additional 18 months, for a total of two years -- 500 milligrams of glucosamine three times a day; 400 milligrams of chondroitin sulfate three times a day; or a combination of the two supplements; 200 milligrams of the pain killer celecoxib (Celebrex) daily; or a placebo.
