(RxWiki News) Millions of Americans take glucosamine supplements to help improve cartilage damage in their joints, but a new study suggests the supplements may not be helping.
Researchers found no evidence that glucosamine improved or delayed cartilage deterioration in the knee.
The study showed no improvement in the number of bone marrow lesions, also called bone bruises, between study participants taking glucosamine and those taking a placebo (fake supplement).
The study's authors noted that bone marrow lesions are thought to be one cause of joint pain.
"Consult your doctor to find the best remedy for joint pain."
This study was led by C. Kent Kwoh, MD, of the University of Arizona in Tucson.
Dr. Kwoh and colleagues recruited 210 participants from an arthritis registry in southwestern Pennsylvania.
These participants were diagnosed with mild to moderate pain in one or both knees using the Western Ontario and McMaster Universities pain index (WOMAC). The WOMAC is a standardized questionnaire that is used to determine a patient’s level of discomfort.
The participants were restricted to taking only acetaminophen (Tylenol) for pain during the study and had not taken glucosamine or other dietary supplements for knee pain within the past six months.
The researchers provided participants with either 1,500 mg of glucosamine hydrochloride in a 16-ounce bottle of diet lemonade or a placebo beverage for 24 weeks.
The authors found no evidence that glucosamine was effective at improving joint health when using magnetic resonance imaging (MRI) to measure levels of cartilage damage at the beginning and end of the study.
The data showed that there was less improvement in bone marrow lesions among those taking glucosamine compared to the placebo group after 24 weeks. The differences were statistically insignificant, however, with 70 percent of knees showing no change at all.
This study is the first to examine whether glucosamine could prevent cartilage damage or bone marrow lesions from getting worse.
"Our study found no evidence that drinking a glucosamine supplement reduced knee cartilage damage, relieved pain, or improved function in individuals with chronic knee pain," Dr. Kwoh said in a press statement.
Dr. Kwoh and team noted that their study was limited by its relatively short 24-week study period.
This study was published March 11 in Arthritis & Rheumatology.
This study was funded by the Beverage Institute for Health & Wellness, The Coca-Cola Company and the National Institute of Arthritis, Musculoskeletal and Skin Diseases.
The authors made no disclosures.