Just about everyone you know who exercises or has joint pain has taken glucosamine at one time or another, and most people swear by it. Yet recently several studies have demonstrated that the benefits of glucosamine are overrated. So, are you wasting your money?

Glucosamine, marketed as a nutritional supplement is one of the most frequently taken dietary supplements for the treatment of joint pain and osteoarthritis (OA) worldwide. Many patients claim that it is effective in relieving their symptoms, such as pain and limited range of motion. But now, after a number of prestigious studies have demonstrated no benefit from glucosamine, its value has been rather soundly dismissed.

Glucosamine occurs naturally as a cartilage building block and is an amino sugar that the body produces and distributes in cartilage and other connective tissue.  Of significance glucosamine is needed for the production of glycosaminoglycan and proteoglycans which give cartilage its shock absorber effect. Therefore glucosamine is assumed to have a major role in supporting healthy cartilage. Glucosamine is available in many forms, including glucosamine sulfate, glucosamine hydrochloride (HCl), and N-acetylglucosamine (NAG), and may also contain a potassium chloride or sodium chloride salt.

Chondroitin, often paired with glucosamine in supplements, is a complex carbohydrate that helps cartilage retain water. Glucosamine and chondroitin are sold as dietary supplements, which are regulated as foods rather than drugs and chondroitin is typically sold as chondroitin sulfate.Glucosamine had been in use with animals, especially horses and dogs, for decades before emerging into prominence as an arthritis treatment for humans. The veterinary community has long embraced its value in treating joint problems in animals.

In 1997, the use of glucosamine grew rapidly after being featured in the book, The Arthritis Cure, by Jason Theodasakis, MD.  He described the use of chondroprotective agents like glucosamine sulfate and chondroitin sulfate as effective agents for the treatment of OA.  He even stated that these agents could actually reduce the structural damage of the articular cartilage. People began using glucosamine as a nutritional supplement and the anecdotal evidence of its effectiveness has been growing ever since.¹

Today, glucosamine is a major market force, though showing some signs of slowing, a trend that is likely to continue and probably accelerate. The global glucosamine market was valued at $2 billion in 2008. Out of that, U.S. sales accounted for $872 million. The second largest market is Japan, which recorded sales of $300 million in sales last year. In addition, per capita spending on glucosamine in the U.S. is very high, ranking fifth globally. Consumers seem to be voting their agreement with glucosamine’s effectiveness with their wallets.²

Most people who take glucosamine are attempting to ease the pain and disability of osteoarthritis.

Osteoarthritis, also called degenerative joint disease is caused by the breakdown of cartilage and causes pain, joint damage, and limited motion. The disease generally occurs late in life, and most commonly affects the hands and large weight-bearing joints, such as the knees. 

An estimated 21 million adults in the United States and 2 million in Canada live with osteoarthritis—the most common type of arthritis. Age, female gender, and obesity are risk factors for this condition. Osteoarthritis sometimes produces acute inflammation but it most commonly causes degeneration of joint cartilage and formation of bony spurs within various joints. Trauma to the joints, repetitive occupational usage, and obesity are risk factors. Although the main goal of glucosamine is to relieve pain, glucosamine was also believed to not only reduce pain but to encourage the growth of new and healthy cartilage, essentially reversing some of the debilitating effects of the disease.

Glucosamine has been studied for four decades with the first published study from Germany in 1969.

Additional studies were performed in Europe and Asia in the 1980’s. These studies compared glucosamine to non-steroidal anti-inflammatory drugs (NSAIDS), the typical medications used to relieve symptoms of OA.  A 2003 meta-study (a study that gathers and compares the results of other studies) by a Belgian research group led by Richy and published in 2003 in the respected journal, Archives of Internal Medicine, found that there was a clear benefit from using glucosamine. These studies correlated well with the enormous stock of positive anecdotal reviews from people who have used glucosamine or a glucosamine-chondroitin combination.³

Such promising results prompted in 2006 the first large-scale multi center clinical trial in the United States  GAIT -Glucosamine/chondroitin Arthritis Intervention Trail to test the effects of the dietary supplements glucosamine hydrochloride (glucosamine) and sodium chondroitin sulfate (chondroitin sulfate) for the treatment of knee osteoarthritis.⁴

It was directed by The National Center for Complementary and Alternative Medicine (NCCAM) and the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), two components of the National Institutes of Health (NIH). The study tested whether glucosamine and chondroitin sulfate used separately or in combination reduced pain in participants with knee osteoarthritis. This study, carefully constructed and carried out, essentially undercut most of the prior research done on glucosamine.

The GAIT study results basically say that glucosamine simply doesn’t work to relieve the pain of osteoarthritis.⁵

A total of 1,583 people participated in the study. People age 40 or older with knee pain and documented x-ray evidence of osteoarthritis were eligible to participate. The study tested the effects of glucosamine alone, chondroitin alone, glucosamine and chondroitin together, celecoxib (brand name Celebrex) and a placebo.

Participants were placed randomly into one of five groups. The study took place in sixteen arthritis treatment centers across the country. The initial study was six months in duration and participants could then elect to continue treatment for another eighteen months.

The doses used in GAIT were based on the doses seen most commonly in the  scientific literature. 

1. Glucosamine alone: 1500 mg daily given as 500 mg three times a day
2. Chondroitin sulfate alone: 1200 mg daily given as 400 mg three times a day
3. Glucosamine plus chondroitin sulfate combined: same doses-1500 mg and 1200 mg daily
4. Celecoxib: 200 mg daily
5. Placebo

Researchers found that:

1. Participants taking the positive control, celecoxib, experienced statistically significant pain relief versus placebo—about 70 percent of those taking celecoxib had a 20 percent or greater reduction in pain versus about 60 percent for placebo.
2. Overall, there were no significant differences between the other treatments tested and placebo.
3. For a subset of participants with moderate-to-severe pain, glucosamine combined with chondroitin sulfate provided statistically significant pain relief compared with placebo—about 79 percent had a 20 percent or greater reduction in pain versus about 54 percent for placebo. According to the researchers, because of the small size of this subgroup these findings should be considered preliminary and need to be confirmed in further studies.
4. For participants in the mild pain subset, glucosamine and chondroitin sulfate together or alone did not provide statistically significant pain relief. 

And the 2010 Swiss study also supports the GAIT study.

Researchers at the University of Bern, Switzerland in 2010 conducted a review and meta analysis of trials examining glucosamine and/or chondroitin for improvements of joint pain and radiological progression in osteoarthritis of the hip or knee.⁶

Relevant databases up through June 2010 were searched for larger-scale randomized controlled trials enrolling patients with osteoarthritis of the knee or hip and comparing glucosamine, chondroitin, or their combination with placebo or head to head. The researchers discovered ten eligible trials, including a total 3,803 patients. They stated their conclusions plainly, saying, “Compared with placebo, glucosamine, chondroitin, and their combination do not reduce joint pain or have an impact on narrowing of joint space,” as reported in the British Medical Journal.

Their meta analysis determined that there was no statistically significant benefit in taking glucosamine or chondroitin. The study sent ripples through the European supplement industry when they went on to say that “Health authorities and health insurers should not cover the costs of these preparations, and new prescriptions to patients who have not received treatment should be discouraged.”

However, the Swiss study in particular has been strongly criticized as having the typical limitations of a meta-study, i.e., comparing trials involving different forms of glucosamine, different severities of condition and different supplementation periods to arrive at an “average” conclusion. Moreover, and possibly most persuasive, those who criticize these studies suggest that they both dismiss the enormous body of anecdotal evidence of benefit from people across the globe as placebo or natural recovery. That’s not plausible, they say, given the sheer numbers of success stories.

Nonetheless, these results are being widely accepted and it is unlikely that there will be further testing of glucosamine.

The Bottom Line

So what do you do? Throw away your glucosamine/chondroitin supplements? Ignore the evidence? The good news in all these findings is that none of the studies have determined that glucosamine (or chondroitin) are in any way harmful. They have also determined that in some limited cases, the supplements do help people.

If you find it helpful, then by all means continue to take glucosamine and chondroitin. But, shop around for the best deal. Consumer Reports says that in general, these products contain the amounts that are advertised on the bottle and that there is little difference among brands.

Could you still be wasting your money? Maybe!

Published January 3, 2011, updated May 25, 2012

References

1. History of Glucosamine, Complementary and Alternative Medicine, Creighton University Medical Center
2. Heller L, Why US Glucosamine Sales are Slow, Nutragredients-USA, Mar 6, 2009
3. Florent R, Structural and Symptomatic Efficacy of Glucosamine and Chondroitin in Knee Osteoarthritis: Arch Intern Med. 2003;163(13):1514-1522. doi:10.1001/archinte.163.13.1514
4. Questions and Answers: NIH Glucosamine/Chondroitin Arthritis Intervention Trial Primary Study, National Center for Complementary and Alternative Medicine, National Institutes of Health, October 2008
5. Barrett S, Glucosamine and Chondroitin for Arthritis: Benefit is Unlikely, Quackwatch, July 22, 2010
6. Wandel et al, Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis, BMJ 2010; 341:c4675

Susan M. Brissette brings 30 years of experience in healthcare, ranging from positions as Chief Executive Officer and Chief Operating Officer in the acute care hospital setting to Senior Executive for a major national healthcare management company. Ms. Brissette holds a BS in Biology from Northeastern University and an MS in Health Policy & Management from the Harvard School of Public Health. She has lectured on healthcare management at the University of Massachusetts, developed a healthcare delivery system for a mining company in Cajamarca, Peru, and recently led the Afghanistan Public Health Redevelopment Task Force for the Washington Harvard Alumni Group. She has consulted on healthcare projects in Poland, Romania, Israel, Kuwait, Peru, Canada, and Mexico. She now owns and operates SB Cass Associates, a healthcare consulting firm located in upstate New York. Ms. Brissette’s consulting practice handles client projects ranging from business plan development for clinics, assisted living facilities, and clinical research groups to the development of market research reports for the pharmaceutical and biotechnology industries. She has written dozens of healthcare articles published on the internet and in national professional and consumer journals. She has also authored or edited online courses on HIPAA compliance, corporate security, childhood obesity, and business ethics.

Susan Brissette can be reached at SB Cass Associates [email protected]