Do Glucosamine & Chondroitin Really Work?
"The public gets information in little, fragmented pieces through the news," says Dr. Walter Willett, a nutrition professor at Harvard University's School of Public Health. "If that's really all they are getting, it is extraordinarily difficult to make some sense out of what's there."
Here's a quiz. Choose the correct answer regarding the recently published study in the New England Journal of Medicine about the role of glucosamine and chondroitin in knee arthritis:
a) Supplements Fail to Stop Arthritis Pain (New York Times)
b) NEJM Study Shows Supplements Relieve Mild Forms of Arthritis (NNFA - the National Nutritional Foods Association)
c) Supplements lose luster after studies question claims (MSNBC)
d) Supplements May Not Help Arthritis (CBS News)
e) Headlines are not fully accurate. Since I am a reader of Dr. Sahelian's outstanding newsletter, I have learned by now not to rely on the headlines of health articles (or headlines of any article on any topic). I only trust the wise opinion of Dr. Sahelian :)
My guess is that practically all of you did well on this quiz by choosing the correct answer, e. I was planning to review the saw palmetto study that I mentioned last time, but we have had so many emails on the glucosamine results that I will bump the saw palmetto analysis for the next issue. In the meantime, I do wish to mention that I am still a believer in saw palmetto. If there's room in the next issue, I will also discuss the calcium and osteoporosis study.
Glucosamine and Chondroitin - One Study, Dozens of Interpretations
We have had many emails requesting my opinion on this topic. Here's a typical example:
"I really respect your opinions and find your site VERY informative. I just read an article on WebMD putting down Glucosamine and Chondroitin. If possible, I'd like to know your opinion. I take both of these nutrients plus MSM and they have been beneficial for me. I'm thinking it's typical conventional medicine thinking-because they can't make money from prescribing these, they put it down. You should write about this and similar "studies" on your site-thanks."
Let's go over the basics of the study. Close to 1600 patients with painful knee osteoarthritis were divided into five groups for a six month study; group A received 1500 mg of glucosamine, group B received 1200 mg of chondroitin sulfate, group C received both glucosamine and chondroitin sulfate, group D received 200 mg of celecoxib (Vioxx), and group E received placebo. The patients were divided into those with mild, moderate and severe arthritis pain but the majority had mild pain. Up to 4000 mg of acetaminophen daily was allowed as rescue analgesia, meaning that patients had the option to take Tylenol if they wanted additional pain relief (to me, this could easily confuse and complicate the findings). Results: For patients with moderate-to-severe pain at baseline, the rate of response was significantly higher with combined glucosamine and chondroitin therapy than with placebo (79 percent vs. 54 percent). (By the way, the fact that 54 percent of placebo patients had a reduction in pain indicates something was not right with this study, perhaps the inclusion of Tylenol for pain relief. Fifty-four percent is too high for a placebo effect and makes me question how well the study was designed.)
This is what the researchers conclude: "Glucosamine and chondroitin sulfate alone or in combination did not reduce pain effectively in the overall group of patients with osteoarthritis of the knee. Exploratory analyses suggest that the combination of glucosamine and chondroitin sulfate may be effective in the subgroup of patients with moderate-to-severe knee pain."
Now, it appears quite clear that these nutrients were effective even at 6 months. Previous studies with these nutrients have indicated that sometimes it takes a year or two for the cartilage in the knees to repair more fully. Why, then, did the media put out headlines that said these supplements did not work? I don't get it. Is it stupidity, lack of ability to read and interpret the results of a study, or just plain and purposeful misleading of the public due to conspiracy with drug companies? I just don't know.
Here is some additional details regarding the interpretation of this study published in the media. It all reminds me of the children's fable of three blind men who are examining an elephant by touch. One blind man, while touching the elephant's side, declares that it was a wall. The second touching its leg, declares the elephant was a tree, and the third blind man, while holding on to it's tail declares the elephant was a snake.
NNFA
This is what the National Nutritional Foods Association (NNFA), a leading trade organization that speaks for vitamin companies, says, "Popular over-the-counter supplements found to provide significant pain relief. A study published in today’s edition of the New England Journal of Medicine (NEJM) suggesting that two very popular supplements— glucosamine and chondroitin sulfate—provide significant pain relief is very positive news for thousands of arthritis sufferers.
CBS News (AP)
Two hot-selling supplements used by millions of Americans are of little help to most people with mild arthritis, concludes a large government study that is part of an effort to scrutinize unproven health remedies. For most arthritis patients with aching knees, the health food store supplements glucosamine and chondroitin sulfate turned out to be no better than dummy pills. People who had more acute knee pain seemed to show some benefit.
A press release from Leiner a vitamin company that sells supplements
Results of a National Institutes of Health (NIH) study published in the February 23rd issue of The New England Journal of Medicine (NEJM) found that taking popular nutritional supplements, glucosamine and chondroitin sulfate in combination, is more effective than pain medication, Celebrex®, in treating moderate to severe osteoarthritis knee pain. For the 21 million Americans suffering from osteoarthritis, the results provide hope to osteoarthritis sufferers in search of pain relief and alternate options to expensive pain medications.
Associated Press - Despite Tests, Many Consumers Swear by Remedies
Last week, major government-funded research indicated that two wildly popular arthritis pills, glucosamine and chondroitin, did no better than dummy pills at relieving mild arthritis pain. While most people taking the arthritis pills in the study got no significant benefit, the pills did appear to help those with more severe pain.
NEJM editorial
An actual editorial published in the same journal that found these nutrients helped with moderate to severe pain, says, "On the basis of these results, it seems prudent to tell our patients with symptomatic osteoarthritis of the knee that neither glucosamine hydrochloride nor chondroitin sulfate alone has been shown to be more efficacious than placebo for the treatment of knee pain."
My Interpretation:
I just don't understand how the NEJM editorial can make a statement that contradicts the findings of the study. Is it because their advertising dollars come from drug companies? The NEJM does not have ads for arthritis supplements but they have ads for arthritis drugs. Case closed. If someday the NEJM starts publishing ads involving arthritis supplements, you will likely see a more positive spin by the editors. Money influences opinions whether in Washington DC or the editorial office of a medical journal.
I think this is a positive study and deserved a more positive spin than what the major media reported. I wonder why the researchers allowed the study participants to use acetaminophen since this drug may damage cartilage tissue, is not very effective in osteoarthritis pain, has liver toxicity potential and may have masked the pain relief obtained by glucosamine and chondrotiin.
Nevertheless, this and dozens of previous studies that support the use of these nutrients for osteoarthritis, continue to convince me that they are a great addition or a good alternative to current NSAIDs, Cox 2 inhibitors or acetaminophen. For more information, see http://www.raysahelian.com/osteoarthritis.html
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