In a just-released study of a daily glucosamine drink, researchers found that the supplement did nothing to prevent knee cartilage deterioration, minimize bone bruises, or help with knee pain.
The recent short-term study looked at the effects of glucosamine hydrochloride on 201 adults. The study was just published in the journal Arthritis & Rheumatology.
“Our study found no evidence that drinking the glucosamine supplement reduced knee cartilage damage, relieved pain or improved function in individuals with chronic knee pain,” said the study’s lead author, Dr. C. Kent Kwoh, professor of medicine and medical imaging at the University of Arizona College of Medicine, according to HealthDay News. “We looked at multiple different ways that glucosamine might help,” said Kwoh, who is also director at the University of Arizona Arthritis Center. “None of them showed any benefit.”
Naturally occurring in humans and other animals, glucosamine helps build cartilage, which is the tissue that cushions bones, according to The LA Times. Glucosamine, in supplement form, is typically manufactured from the shells of sea animals. Marketers have long claimed that glucosamine encourages joint health and also supports cartilage growth. In fact, some 10 percent of the United States population takes glucosamine, according to the study’s authors, wrote The LA Times.
In studies conducted in Europe, where a prescription is required for glucosamine, some manufacturer-funded studies have shown benefits with the supplement. In the U.S., where the supplement is available over-the-counter (OTC), studies have not proven glucosamine’s efficacy in slowing knee osteoarthritis, The LA Times wrote.
The recent study involved a test of glucosamine’s effects on adults aged 35 to 65 who also complained of knee pain. About half of the study participants—98—received daily 1,500 mg doses of glucosamine hydrochloride in a 16-ounce lemonade drink. The other half of the participants—103—received lemonade drinks that did not contain glucosamine hydrochloride, The LA Times reported.
The subjects underwent MRIs at the beginning of the study trial and, again, at 24 weeks. Participants also reported on knee pain and provided urine samples, which involved testing for C-terminal cross-linking telopeptide of type II collagen (CTX-11). This is a molecular marker for degradation of cartilage tissue, according to The LA Times. The authors concluded that the testing did not provide evidence that glucosamine provided increased efficacy when compared to the placebo in improving participants’ joint pain.
Millions of Americans take glucosamine for the treatment of osteoarthritis of the knee joints, as well as other joints. Osteoarthritis is the most common form of arthritis, which is associated with normal joint wear and tear, according to HealthDay News. Glucosamine is generally sold as either glucosamine hydrochloride or glucosamine sulfate. Some say the different forms may affect joints in different ways; however, Kwoh says that pharmacological studies reveal no difference between the two options, wrote The LA Times.
According to the researchers, this was the first study to use MRIs to look at the effects of glucosamine on bone marrow lesions and cartilage. Prior research utilized X-rays, but X-rays only show bones, not cartilage. Physicians determine the health of invisible cartilage by measuring the distance between the bones of the knee; longer distances point to increased cartilage. Kwoh said that using MRI technology enabled his team to more directly examine the cartilage, according to The LA Times.
