Comments on Joint Supplements

In the November 2000 issue of The Horse, an article discusses equine joint supplements and the "most controversial areas of supplementation." The article unfortunately further clouds a very complicated situation. The real issue for consumers is how to distinguish a quality joint supplement from the flood of "low-quality" products in the market. A study published in the Journal of the American Nutraceutical Association showed that 84% of human over-the-counter glucosamine/chondroitin sulfate products do not meet label claim. There is no reason to believe that in a similarly unregulated climate, supplements for animals would be maufactured to higher standards. Laboratory analysis of many equine and small animal products performed by Nutramax confirms this notion.

Nutramax Laboratories patented and brought to market the combination of glucosamine, chondroitin sulfate, and manganese ascorbate in its joint supplements Cosamin (for humans) and Cosequin (for animals). These brands are the only combination products that have been proven effective in published, double-blind, placebo controlled U.S. studies (see page 93 for a listing of studies). Additionally, numerous scientific publications name Cosequin/Cosamin as being analyzed to meet label claim. Nutramax is a leader in setting high manufacturing and quality control standards in the unregulated supplement industry. This article did not attempt to differentiate high-quality products from "look-alike, low quality" products that lack scientific data to support their use.

The article states, "These products escape regulation as drugs by means of clever packaging and vague claims..." We agree that many products make unsubstantiated claims such as "cures arthritis," "develops mature cartilage," "dramatic results in five days," "works in 20 minutes," and "guaranteed results." It is important to note that chondroitin sulfate and glucosamine are legally marketed as human dietary supplements, but laws that govern human dietary supplements do not include animals. However, the FDA's Center for Veterinary Medicine (CVM) is working to develop a dietary supplement category for animals.

The article also states, "But the hard, unvarnished truth of it is that oral joint supplements still have very little proof of efficacy..." Although most supplements do not have any research, published clinical studies in rats, rabbits, dogs, humans, and horses confirm both product safety and efficacy for Cosequin and Cosamin. The robustness of product efficacy can be determined by the repeatability of results, over time, in different species, under different clinical or laboratory model conditions. Recently, The Journal of The American Medical Association published a report showing that in human trials, the 95% low molecular weight chondroitin sulfate (exclusive to Cosequin/Cosamin) had a larger treatment effect than glucosamine alone.

Many products claim to be "better absorbed;" however, no absorption studies are available for those products. Absorption studies in dogs have been completed for Cosequin showing that the material is bioavailable. Comparative studies evaluating the chondroitin sulfate in Cosequin against other grades of chondroitin sulfate show the low molecular weight material in Cosequin has the best permeability profile, which is an indicator of absorption.

Equine absorption studies have been completed and will be published next year. These results show that Cosequin is absorbed, which is a claim no other manufacturer can make.

As a company, we are frustrated that our competitors, who use untested, lower-quality ingredients in their products, have chosen to cite studies that apply only to Cosequin. For nearly a decade, Nutramax has differentiated ourselves from our competitors by having strong scientific support for our products, using the highest quality raw materials, and exercising higher manufacturing standards than is typical for our industry.

The article concludes that a horse owner should consult his or her veterinarian before administering a supplement, and we heartily endorse that notion. That is why Cosequin is sold only by veterinarians. Many horse owners waste money by self-treating their horses with a joint supplement when the problem may not involve joint cartilage.

We applaud The Horse for presenting a realistic scenario of the veterinary dietary supplement industry; however, we wish the article had presented more suggestions for horse owners on how to evaluate products.

The Arthritis Foundation's Guide to Alternative Therapies gives this advice: "When a supplement has been studied with good results, find out which brand was used in the study, and buy that." Since there are several substandard oral joint supplement products on the market, horse owners need to seek out the scientific facts about joint supplements so that they can make educated decisions.

Todd Henderson, DVM, and Judy Downer, PhD, Research Division, Nutramax Laboratories, Inc., 2208 Lakeside Blvd., Edgewood, Md. 21040; 800/925-5187;

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