GlucoChondro, A No Show?

Here is a copy of a paper I wrote for my Sports Nutrition class last semester regarding Glucosamine and Chondroitin supplementation. A week or so after I turned in the paper I came across this web page, which provides the research that the NCCAM has found on the effectiveness of GlucoChondro.

Non-steroidal anti-inflammatory drugs (NSAIDs) have been a popular choice for athletes to relieve their joint pain and other symptoms of osteoarthritis. These drugs are great for providing relief for short periods of time, but have some negative effects that can delay injury recovery if taken long-term. (4) One alternative to NSAIDs that has been suggested in the last decade is glucosamine/chondroitin supplementation. It is believed that glucosamine helps in the formation of cartilage as well as its repair.  Chondroitin has a similar function and helps with the elasticity of cartilage. Glucosamine and chondroitin sulfate are chemicals that are naturally produced by the body.  Because their production isn’t dependent on the individual’s diet, it is suggested that supplementation will either increase cartilage growth or decrease its breakdown. (5)  Rock climbers are known for the strain they put on their bodies, especially their joints.  Taking a glucosamine and chondroitin sulfate supplement is strongly encouraged within the climbing community (6,7) to prevent osteoarthritis though the research regarding the effectiveness of such supplementation is conflicting to say the least.

The usual dose for glucosamine and chondroitin is 1500 mg/d and 1200 mg/d respectively. (1,5) The larger doses are due to the fact that the supplement’s bioavailability is only 12 to 21%.  Glucosamine/chondroitin supplementation is relatively safe due to a small number of adverse effects. As a supplement, glucosamine is derived from the exoskeleton of shellfish like shrimp, lobsters, and crabs and can causes allergic reactions in individuals who have seafood allergies. Chondroitin can have a blood-thinning effect and should be avoided by individuals taking blood-thinning medication. Other adverse effects that have been reported are nausea, abdominal pain, headaches, and back pain. (1)

Most of the positive evidence regarding glucosamine/chondroitin supplementation has been obtained from experiments involving animals. Though these studies do not directly related to human patients they do provide information that would be difficult or unethical to obtain from human subjects. One study involving cows used the cartilage and ligament cells surrounding the metacarpals joints as cultures and concluded that glucosamine/chondroitin not only stimulates cartilage growth but ligament growth as well. (4) Another study conducted on rabbits suggests that glucosamine/chondroitin supplementation cannot improve already healthy joints. (2)

A study comparing a mineral supplement, Aquamin, a glucosamine/chondroitin supplement, and a combination of the two in their ability to relieve osteoarthritis pain happened upon some shocking results. This study tested the functional capacity of subjects with moderate to severe osteoarthritis in their knees. Aquamin is a supplement derived from seaweed that contains minerals such as calcium, magnesium, salt, and other trace minerals. The subjects were tested by walking as far as they could until their pain was too much. The distance they could walk was measured several times during the 12 week study.  The study found that Aquamin provided the greatest amount of relief and allowed for the greatest distance of walking, followed by glucosamine and chondroitin, the placebo, and the combination of the two supplements. (8) The performance of the combination treatment suggests the ingredients of the two supplements must be counteractive in one-way or another. This topic would be very interesting to study.  The results of the study should be viewed with caution because Marigot Ltd, the manufacturer of Aquamin, paid for the study.

The clinical practice guideline approved by the American Academy of Orthopedic Surgeons is based on a review of published studies regarding osteoarthritis in the knee. The purpose of the review is to compile a list of recommendations of non-invasive treatments for osteoarthritis. One of these recommendations is to refrain from prescribing glucosamine and chondroitin to patients. This recommendation is based on another review of studies that concludes that glucosamine/chondroitin supplementation doesn’t provide any clinical benefits to the patient but is superior compared to a placebo. Unfortunately, the guidelines do not define clinical importance or specify what clinical benefits are. Though the guidelines do not suggest glucosamine/chondroitin supplementation they do suggest the prescribing on NSAIDs as well as acetaminophen despite the long-term implications. (3)

With this review of the research literature it would be suggested that glucosamine/chondroitin supplementation should only be recommended as a last resort treatment for osteoarthritis.  Supplementation hasn’t been shown to prevent joint injuries or the onset of osteoarthritis so it should only be tried by those that have already suffered injury. Also supplementation should be considered if the duration of injury recovery is longer than the suggested duration of NSAID use to avoid longer delays in recovery. Because research suggests that improvements due to glucosamine/chondroitin supplementation take 6 to 8 weeks to show (1); supplementation should stop after 8 weeks if improvements aren’t noticed.

References
1.     Leburn, CM. GLUCOSAMINE (and Chondroitin). American Journal of Medicine and Sports. 2004 May/June

2.     Bradley-Popovich, G. Sports Injury Management: Do Diet and Supplementation Play a Role?. Strength and Conditioning Journal. 2004 October

3.     Richmond, J; Hunter, D; Irrgang, J; Jones, M; et al. Treatment of Osteoarthritis of the Knee (Nonarthroplasty). Journal of American Orthopedic Surgeons. 2009 September

4.     Lippiello, L. Collagen Synthesis in Tenocytes, Ligament Cells and Chondrocytes Exposed to a Combination of Glucosamine HCl and Chondroitin Sulfate. Advance Access Publication. 2006 December

5.     Dunford, M. Sports Nutrition. American Dietetic Association. 2006

6.     Horst, E. Training for Climbing. Falcon Guide Publishing. 2008

7.     Rosenberg, Thomas. To Supplement or Not To Supplement? Climbing.com

8.     Frestedt, J; Walsh, M; Kuskowski, M; Zenk, J. A natural mineral supplement provides relief from knee osteoarthritis symptoms: a randomized controlled pilot trial. Nutrition Journal. 2008 February