Q: As a runner I have experienced joint pain in my knees and hips. A friend suggested that glucosamine and chondroitin sulfate might be helpful for improving my joints. What information is available about the use of these supplements and are there concerns with taking these supplements?
A: Both glucosamine and chondroitin are found in the body and serve as the major precursors for the structural materials in joints, bones, skin, and blood vessels. Although, the body can make both glucosamine and chondroitin, they may also be purchased as nutritional supplements. When administered orally glucosamine and chondroitin sulfate have been shown to slow degenerative joint disease and improve the symptoms of osteoarthritis. The mechanism by which these compounds slow or reverse degenerative joint disease is due to their ability to act as substrates for the formation of healthy cartilage, the major structural component of joints. Additionally, the use of these supplements has been shown to reduce the use of non-steroidal anti-inflammatory meditations.
Glucosamine is a structural amino-sugar found in tissues, whereas chondroitin is a large protein derived from cartilage. Although they are present normally in our bodies, for the purpose of producing dietary supplements glucosamine and chondroitin are extracted from animal tissues. In general, glucosamine comes from the shells of lobster, crab, and shrimp and chondroitin from animal cartilage. Although the combined use of these supplements has become popular, there is little evidence to suggest that taking them together is better than taking either alone.
Commonly Tolerated Oral Dosage:
glucosamine sulfate - 500 mg/3 times/day for a minimum of 6 weeks
chondroitin sulfate - either 400 mg/2 times/day or 800 mg/day
Considerations:
Consult your physician before taking dietary supplements, particularly if you are diabetic, taking medications for blood thinning (e.g. aspirin or coumadin), or if you’re allergic to shellfish.
Because the dietary supplement industry is not regulated by the government in some cases supplements can vary in composition and quality. Therefore, choose dietary supplements from established companies.
Do not take if you’re a child, pregnant, or think you make be pregnant, as the safety of these supplements has not been tested in these individuals.
Rebecca L. Persinger, RD, CNSD, PhD
Rebecca is active in the Seattle running and cycling communities and enjoys other outdoor activities including: snowshoeing, skiing, mountain biking, and hiking.
