Diet Supplement Glucosamine No Better Than Placebo

Under the dubiously named Dietary Supplement Health and Education Act (DSHEA), diet supplements and herbal preparations are not approved by the Food and Drug Administration for medical use in humans. Thus, safety and formulation are solely the responsibility of the manufacturer; evidence of safety and efficacy is not required as long as they are not advertised as a treatment for a medical condition. As we have seen in diet supplement litigation (Talbert v. E’ola Products, Inc.), diet supplement manufacturers often promise the moon in selling their products to the consumer, while having little other than anecdotes to show when it comes to providing data for the safety or effectiveness of their products. Even assuming that the products are not adulterated (because of shoddy manufacturing protocols), have not been spiked (pharmaceutical drugs intentionally put into the supplement), and actually contain the ingredient at the levels claimed (often the “active” ingredient is missing or varies wildly), it is the exception, not the rule, that the manufacturer will have evidence that the supplement is safe for human consumption and actually works. With pharmaceutical drugs, the manufacturer foots the bill for such research. In the world of diet supplements, however, it is often independent researchers or the government (read: the taxpayer) that is burdened with the duty and cost of proving the safety and efficacy of a particular diet supplement.

At the Alaska Personal Injury Law Group, we are frequently asked to help those with serious orthopedic injuries. And our clients commonly face the debilitating consequences of arthritic changes that come from these injuries. So a discussion about glucosamine is in order. Luckily, unlike ephedra and other more dangerous diet supplements, glucosamine has not had a string of serious adverse events (it is not without side effects, however, so you need to read carefully before using glucosamine). But does it work?

Glucosamine is a natural compound that is found in healthy cartilage. Glucosamine sulfate is a normal constituent of glycoaminoglycans in cartilage matrix and synovial fluid (this is the “hydraulic” fluid in your joints). It is believed that the sulfate moiety provides clinical benefit in the synovial fluid by strengthening cartilage and aiding glycosaminoglycan synthesis. The question is, if you take the supplements, will the body put the critical compounds into your blood stream and use them where the arthritis lies? There have been multiple clinical trials of glucosamine as a medical therapy for osteoarthritis, but the results have been conflicting. Early clinical trials sponsored by a European patentholder, as expected, demonstrated a benefit from glucosamine. However, these studies were of poor quality due to shortcomings in their methods, including small size, short duration, poor analysis of drop-outs, and unclear procedures for blinding. Subsequent independent studies did not detect any benefit of glucosamine. This situation led the National Institutes of Health (yes, you the taxpayer) to fund a large, multicenter clinical trial studying reported pain in osteoarthritis of the knee, comparing groups treated with chondroitin sulfate, glucosamine, and the combination, as well as both placebo and celecoxib (Celebrex). The results of this 6-month trial found that patients taking glucosamine HCl, chondroitin sulfate, or a combination of the two had no statistically significant improvement in their symptoms compared to patients taking a placebo.

Today’s news is that the Annals of Internal Medicine has just published a study concerning the effect of glucosamine sulfate on the symptoms and structural progression of hip arthritis. Following 222 patients over a 2-year period, the researchers evaluated the patients’ pain, function and stiffness at regular intervals in the 2-year period. They concluded that “glucosamine sulfate was no better than placebo in reducing symptoms and progression of hip osteoarthritis.” Translation: glucosamine supplements will do nothing for the pain in your hip-the pain is likely coming from what the cost of the supplements did to your wallet.

Source: Annals of Internal Medicine, Effect of Glucosamine Sulfate On Hip Osteoarthritis, 19 February 2008, Volume 148 Issue 4, at 268-277, http://www.annals.org/cgi/content/abstract/148/4/268.

Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), http://www.clinicaltrials.gov/show/NCT00032890; AND http://www.ncbi.nlm.nih.gov/pubmed/16495392.