I am often asked to give people data about joint supplements due to comments in an earlier post. I am recently returned from a medical conference where current concepts regarding these important supplements were elaborated upon. I think it important for all runners to read this post.
Up until recently, current concepts suggested that Chondroitin Sulfate, a large macro molecule, was not able to be absorbed into the blood stream, and as such, was a useless supplement. We now know that this is not in fact the case, and that chondroitin can be absorbed by as much as 70% into the blood stream. While this is important, it is not as important as the statistically significant study which illustrates that in combination, that is glucosamine plus chondroitin, when taken together, are absorbed at a significantly higher rate than either one by itself. Further, other studies published in 1999 show that when taken together, there is a significant increase in proteoglycan synthesis which remained elevated after five days of continued exposure.
There is more. Animal studies show that joint inflammation is significantly reduced when both are taken together. Also, when taken in combination, cartilage lesions are shown to be significantly reduced. Human studies, of which there are few, demonstrate a significant reduction in osteoarthitis symptoms (wear and tear) with combination treatment. This remained true in a six month follow-up study with statistical significance.
With respect to glucosamine sulfate vs glucoseamine chloride, the chloride version typically results in a more significant dose, and is therefore preferable.
Now for a word on products. There is a huge variation in product quality. A study was presented that evidenced the range of content of products labeled quantity. And I have to tell you that most, if not all of the product on the shelf is suspect. There is very little available product that actually contains the quantity reported on the label. This is especially true in combination products. The variation was as much as between 25% and 115%, but on average, was less than 40%! This is very bad.
By the way, price was not a determining factor!
The product Cosamin DS was clearly the leader in terms of +/- 5% percent of label claim, for both chondroitin and glucosamine. You can learn more at www.cosamin.com, or call (800) 925-5187. By the way, I have no financial relaionship to this product. Also, when tested by batch, the scatter remained the same. Also, it is a price competitive combination product. On price, by the way, products costing less than $1.00/1200 mg was shown to be sub-potent.
Now, with respect to the mechanism.
Most people are interested to know how they can extend their running careers.
I am pleased to report that used in a prophylactic fashion - that is taking it even if you do not hurt - seems to be a worthwhile endeavor. The chemistry is such that because the structures are assembled extracellularly, having both CS and GS in your system is shown to increase the protection of the articular cartilage. This is new information to me, and I am recommending that runners use a combination supplement to help protect their joints from unreasonable damage due to impact loading.