Chondroitin sulfate consists of repeating chains of molecules called glycosaminoglycans
(GAGs). Chondroitin sulfate is a major constituent of cartilage, providing structure, holding water and
nutrients, and allowing other molecules to move through cartilage—an important property,
as there is no blood supply to cartilage.
Where is it found?
The only significant food source of chondroitin sulfate is animal cartilage.
Why do athletes use it?*
Some athletes say that chondroitin sulfate
helps reduce joint pain.
What do the advocates say?*
For a long time, glucosamine dominated the market among supplements used to ease joint
pain. Now, many practitioners prefer to use a combination of both glucosamine and chondroitin
sulfate. Many have found this combination to be effective, particularly for runners, who tend
to develop problems with their knees. Glucosamine and chondroitin sulfate are well absorbed by
the molecules that make up cartilage. They are not available from food. It is not uncommon to
have to take these supplements indefinitely to continue to experience relief.
Recent research has shown that the results of arthroscopic surgery for osteoarthritis in
the knee is no different than that of placebo. This gives people further reason to at least
give supplements, such as chondroitin sulfate, a try before enduring more invasive, expensive
approaches.
How much is usually taken by athletes?
Chondroitin sulfate, 800 to 1,200 mg per day, is effective for reducing joint pain caused
by osteoarthritis.12 Other uses of chondroitin sulfate for sports and
fitness, including prevention of joint pain or treatment of sports injuries, have not been
studied.
Are there any side effects or interactions?
Nausea may occur at intakes greater than 10 grams per day. No other adverse effects have
been reported.
One doctor has raised a concern that chondroitin sulfate should not be used by men with prostate cancer. This concern is based upon two
studies. In one, the concentration of chondroitin sulfate was found to be higher in cancerous
prostate tissue as compared to normal prostate tissue.3 In the other study, it was
shown that higher concentrations of chondroitin sulfate in the tissue surrounding a cancerous
prostate tumor predict a higher rate of recurrence of the cancer after surgery.4 However, no studies
to date have addressed the question of whether taking chondroitin sulfate supplements could
promote the development of prostate cancer. Simply because a substance is present in or around
cancerous tissue does not by itself suggest that that substance is causing the cancer. For
example, calcium is a component of
atherosclerotic plaques that harden the arteries; however, there is no evidence that taking
calcium supplements causes atherosclerosis. To provide meaningful information, further studies
would need to track the incidence of prostate cancer in men taking chondroitin supplements.
Until then, most nutritionally-oriented doctors remain unconcerned about this issue.
It is not known whether taking glucosamine
sulfate and chondroitin sulfate in combination is a more effective treatment for osteoarthritis than taking either one by itself.
At the time of writing, there were no well-known drug interactions
with chondroitin sulfate.
*Athletes and fitness advocates may claim benefits for chondroitin
sulfate based on their personal or professional experience. These are individual opinions and
testimonials that may or may not be supported by controlled clinical studies or published
scientific articles on chondroitin sulfate. For more complete and detailed information,
including references and safety information, see
Chondroitin Sulfate as a nutritional supplement.
References (To view, roll mouse over the "References" heading; to hide, click on the heading)
1. Leeb BF, Schweitzer H, Montag K, Smolen JS. A meta-analysis of
chondroitin sulfate in the treatment of osteoarthritis. J Rheumatol
2000;27:205–11.
2. McAlindon TE, LaValley MP, Gulin JP, Felson DT. Glucosamine and
chondroitin for treatment of osteoarthritis: a systematic quality assessment and
meta-analysis. JAMA 2000;283:1469–75 [review].
3. De Klerk DP, Lee DV, Human HJ. Glycosaminoglycans of human prostatic
cancer. J Urol 1984;131:1008–12.
4. Ricciardelli C, Quinn DI, Raymond WA, et al. Elevated levels of
peritumoral chondroitin sulfate are predictive of poor prognosis in patients treated by
radical prostatectomy for early-stage prostate cancer. Cancer Res
1999;59:2324–8.
The information presented in Healthnotes is for informational purposes
only. It is based on scientific studies (human, animal, or in vitro), clinical
experience, or traditional usage as cited in each article. The results reported may not
necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over the counter medication is also available. Consult your doctor,
practitioner, and/or pharmacist for any health problem and before using any supplements or
before making any changes in prescribed medications. Information expires September 2008.
