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| WHAT ARE NUTRITIONAL SUPPLEMENTS? |

To date, there is no ‘cure’ for arthritis. The best that we know how to do is to treat the symptoms- pain, loss of flexibility, etc. As a result, arthritis patients have searched for alternatives to conventional (i.e., medically prescribed) treatments. Some of these treatments include Chinese herbs, DMSO, ginger, ginkgo, St. John’s Wort, etc. The sources of many of these therapies are biological – i.e., plant or animal derived and are, therefore, frequently labeled as "natural" remedies or treatments. There is a book published by the Arthritis Foundation that describes many of these therapies (Horstman, Judith: The Arthritis Foundation’s guide to Alternative Therapies, 1999). On the one hand, one must be wary of treatments called "cures" or "miracle treatments", while on the other hand one needs to evaluate carefully the criticisms of the "skeptics."

Chondroitin Sulfate and Glucosamine

The healthy cartilage covering the ends of bones is called hyaline or articular cartilage. The cartilage, along with the fluid in the joint, works to permit movement of long bones next to each other (e.g. thigh bone vs. shin bone). Cartilage is made up of cells (called chondrocytes) and the material that surrounds the cells (called matrix). Cartilage is approximately 95% matrix and 5% cells. The matrix is made up of collagen, a protein, and glycosaminoglycans, a type of carbohydrate molecule. Glucosamine and chondroitin sulfate are two molecules found in articular cartilage. Chondroitin sulfate is the most abundant glycosaminoglycan (GAG) in cartilage. It binds to the collagen-giving cartilage its unique characteristics – strength, flexibility, slipperiness.

Research

Numerous studies have been conducted to evaluate the response of cartilage and, specifically, cartilage cells to treatment with glucosamine and chondroitin sulfate. Laboratory studies have shown that glucosamine stimulates cartilage cells and the production of GAGs in articular cartilage. Likewise, laboratory studies have shown chondroitin sulfate can act to inhibit many of the enzymes that work to break down the cartilage and fluid in the knee joint.

A large number of clinical studies have been conducted in Europe and other countries outside of the United States. Although the FDA does not require studies to be conducted on nutritional supplements, a few studies have been completed in the United States evaluating the effectiveness of a glucosamine and chondroitin sulfate in the treatment of osteoarthritis. Das et al. reported on 93 patients with knee osteoarthritis at the Annual Meeting of the American Academy of Orthopaedic Surgeons in 1999. They found a significant functional improvement in the treated patients as compared to placebo-based controls. Leffler et al. reported similar findings in OA patients with back or knee involvement (Military Medicine, 164: 85-91, 1999). Currently, a double-blind, placebo-controlled study is underway at the Johns Hopkins University School of Medicine to evaluate the use of the combination therapy. If you live in the Baltimore area and have arthritis of the knee you can participate in this study.

Questions Concerning Chondroitin Sulfate/Glucosamine Combination Therapy

  1. Does it matter which product you use?

  2. A recent study published by Adebowale, et al. (Journal of the American Nutraceutical Association, 3: 37-44, 2000) reported on the analysis of the content of glucosamine and chondroitin sulfate in 14 products and chondroitin sulfate in 43 products. They found a significant variation in the amount of each molecule in the products tested. These amounts were significantly different from the content listed on the product label. Furthermore, the less expensive a product was (i.e., less than or equal to $1.00/1200 mg), the more deficient the product was.

    Why is this a concern? A patient may try an over-the-counter product and decide that glucosamine/chondroitin sulfate does not work for them. However, it may be that the product that they tried was of poor quality. If a higher quality (i.e., product containing a product of higher purity and content) was taken, they might have experienced a favorable response.

  3. Is chondroitin sulfate/glucosamine safe?
  4. Based upon current knowledge, there are no significant side effects to taking either chondroitin sulfate or glucosamine.

  5. What dose should you use?

  6. It is recommended by one of the manufacturers (Nutramax Laboratories, Inc.) that each individual takes 1500-mg glucosamine and 1200-mg chondroitin sulfate/day. They state that this may be decreased after 60 days. However, additional study is warranted to evaluate the effect of different doses (concentrations) and dose regimens (frequency of dose).

  7. Will I see an immediate effect?

  8. Probably not. Multiple studies have shown a delay from the onset of treatment to the time of symptom relief. It is possible that you may not see an effect for three to four months.

  9. Can individuals with diabetes use this treatment?

  10. There has been recent articles suggesting that glucosamine treatment may increase the risk of diabetes. This study involved only 16 patients. It was widely reported via the internet. Thousands of patients have been studied. No published study has recorded any impact on the incidence of diabetes of the course of diabetes.

  11. There is a concern that patients will stop taking OA therapies known to be effective in favor of yet-to-be proven supplements.

    There are no known "effective" OA therapies to treat the skeletal changes that occur- only the symptoms. However, it is important for each person to visit a physician to determine that they do have osteoarthritis. "Self treatment" of osteoarthritis is not nearly as big a concern as "self diagnosis." If you have symptoms of recent onset for which a diagnosis has not [yet] been made, you should see your doctor for the purposes of diagnosis.