Does glucosamine in its various forms actually work?
Americans spend approximately $1 billion each year on various forms of glucosamine supplements, primarily for the treatment of osteoarthritis. Is that money well spent, or wasted?
A review of the published research is included below. In summary, clinical trials published to date have shown inconsistent results, but taken together suggest that glucosamine and chondroitin supplements provide a modest benefit to those who suffer with osteoarthritis.
I personally believe that glucosamine and chondroitin supplements can be, and are, very beneficial to some percent of those suffering with osteoarthritis. My opinion is based almost entirely on my conversations with those who have used these supplements to obtain meaningful relief from osteoarthritis.
In addition, common sense argues that a product consistently generating annual sales of nearly $1 billion is probably ‘doing something.’
However, I believe that glucosamine and chondroitin supplements only help about 30% of those who use them. Again, my estimate is not scientific, but is based entirely on my general observations and conversations I have had with osteoarthritis sufferers.
But if these supplements are effective for 30% and not for others, that fact might explain why clinical trials do a poor job of showing efficacy. The 30% of responders, when averaged with 70% non-responders, would on average show only a modest, or no, improvement – when in fact a select few might experience substantial improvement.
One significant drawback to these supplements is that they must be used for three months before the user can say if they are working or not.
Three months is a long time to wait and see. A substantial cost is associated with that three month delay – in terms of both money and time spent suffering – especially if your conclusion at the end of three months is that the product does nothing for you.
Nonetheless, given that many people have had good results, and that there are no significant side effects associated with these supplements, a three month personal trial is recommended as a reasonable way to discover for yourself if glucosamine and chondroitin supplements are effective – for you.
The clinical effectiveness of glucosamine and chondroitin supplements in slowing or arresting progression of osteoarthritis of the knee: a systematic review and economic evaluation.
Summary of the abstract
The clinical effectiveness and cost-effectiveness of glucosamine and chondroitin sulphate in osteoarthritis of the knee was evaluated.
A search was conducted for systematic reviews of randomized controlled trials of at least a year in length. Five systematic reviews were identified. They reported inconsistent conclusions with only modest effects on reported pain and function.
A separate review of eight primary trials of at least a year showed evidence of statistically significant improvements in joint space loss, pain and function for glucosamine sulphate, but the clinical significance of these differences was not clear. In two studies of glucosamine sulfate, the need for knee arthroplasty was reduced slightly.
For other preparations of glucosamine, chondroitin and combination therapy, there was less evidence to support a clinical effect.
In conclusion, there was some evidence found that glucosamine sulphate may be somewhat effective in the treatment of osteoarthritis of the knee. The biological mechanism of action remains uncertain.