New Studies Give Mixed Signals About Glucosamine, Chondroitin Benefits
Nov. 14, 2005 -- Arthritis sufferers may -- or may not -- benefit from a pair of popular dietary supplements, two new clinical trials suggest.
One supplement is glucosamine, derived from the shells of crabs and lobsters. The other is chondroitin, usually derived from animal cartilage. These supplements are said to help relieve arthritis pain. They are also said to prevent the arthritic joint narrowing that causes one bone to grind against another.
Do these supplements really work? That is what two clinical trials -- a 1,583 patient study in the U.S. and a 318 patient study in Europe -- tried to find out. Researchers reported results from both studies at this week's annual scientific meeting of the American College of Rheumatology in San Diego.
"The supplements were not better than the placebo," Daniel O. Clegg, MD, tells WebMD. Clegg, chief of rheumatology at the University of Utah in Salt Lake City, led the NIH-sponsored U.S. study.
Arthritis Foundation spokesman Erin Arnold, MD, has a different interpretation. Arnold, a rheumatologist with the Illinois Bone and Joint Institute in Morton Grove, Ill., notes that Clegg is focusing on the study's overall results. She says she is more impressed with the study's finding that patients with more severe arthritis pain got significant relief from the glucosamine-chondroitin combination.
"I am very encouraged by the results of this study," Arnold tells WebMD. "The data presented certainly does not deter me from encouraging patients to try glucosamine and chondroitin."
There is less controversy over the smaller, European study led by Gabriel Herrero-Beaumont, MD, of the Jiminez Diaz Foundation in Madrid, Spain.
"Our results confirm previous studies," Herrero-Beaumont tells WebMD. "They demonstrate clearly that glucosamine was able to control knee osteoarthritis pain."
Glucosamine + Chondroitin: For Bad Arthritis Pain Only?
The U.S. trial enrolled patients aged 40 and older with knee pain due to osteoarthritis. They were randomly assigned to one of five treatments:
- Inactive placebo pills
- Glucosamine hydrochloride at a dose of 500 milligrams three times a day
- Sodium chondroitin at a dose of 400 milligrams three times a day
- Combination glucosamine and chondroitin
- Celebrex at a dose of 200 milligrams per day