One of the strongest-selling categories in dietary supplements has been joint health, a soft term for management of osteoarthritis (OA) and chronic joint pain. Nutrition Business Journal has assessed this category to exceed $1.5 billion in consumer sales annually.
Leading this category have been the glucosamine forms of hydrochloride (GCl), sulfate (GS) and N-acetyl-glucosamine (NAG). The strongest clinical evidence of efficacy resides with a single, specific GS form manufactured by Rotta Laboratories in Italy (branded under the DONA, Viartril-S or Xicil names in the EU and North America).1,2,3,4
Their composition describes a sodium chloride salt of GS, with the ?G? being derived from shellfish biomass. The ratio of the constituents in this composition is 2(G):1(S):2 (sodium):2(chloride). The sodium chloride is added to stabilise the GS, which alone tends to absorb ambient moisture.
One question that likely will remain enigmatic is whether GCl is pharmacoequivalent to the innovator material embodied in Rotta?s GS. To date, no large sample size, long-term (equal to or greater than six months) head-to-head comparator studies have been conducted with a study design that can address this question.
From an EU perspective, the European Food Supplements Directive is poised to alter the joint health products landscape. One of the provisions of the Directive is mandatory declaration of the origin of any agent that is derived from a potential allergen category. This immediately invokes glucosamine products that are derived from crustaceae. This provision is expected to be in force by 2005 and apply to companies both manufacturing and marketing in the EU.
It is thus timely that non-shellfish origin glucosamine is entering commerce. Suspected glucosamine-mediated allergic reactions appear to be very rare.5,6 Still, the option of a shellfish-free ingredient may prove appealing to some consumers.
Shellfish-free On The Market
Both Cargill and Arkion Life Sciences have shellfish-free, Kosher-approved GCl in queue. Cargill has begun marketing its Regenasure brand GCl, which starts from corn-derived glucose and is subjected to microbial fermentation. Arkion?s ingredient also starts from corn, but appears to be produced via fermentation with a genetically modified microorganism, as described in its US patent. (Arkion has licensed its process technology to a separate entity for commercialisation, with an indefinite launch date.)
A different approach to providing glucosamine has been embraced by one of the world?s largest chicken producers, Tyson Foods, which is licensing a patented process whereby vertebrate (the patent claims bovine source) connective tissue is disintegrated and then thermally processed. The resulting liquid can then be added to a variety of physical food delivery forms, containing chondroitin and glucosamine, and which may be allowable for sale as a food.
The largest study to date examining the comparative efficacy of glucosamine to other agents for OA is being sponsored by the National Institutes of Health in the US. The Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT) pits GCl against chondroitin sulfate (CS), celecoxib (Celebrex, a prescription COX-2 inhibitor and treatment for OA), the combination of GCl and CS, and placebo. The GCl that was selected is derived from shellfish and is produced by Pfanstiehl Laboratories (Illinois, US). The full two-year study results will be published in 2006.
The outcomes have the potential of creating either a devastating tectonic plate shift in the evidence foundation for GCl and chondroitin sulfate or could usher in a renaissance in awareness and demand for these natural chondroprotective agents.
Anthony Almada, MSc, is the president and chief scientific officer of IMAGINutrition Inc and has been a co-investigator on more than 60 randomised controlled trials. www.imaginutrition.com
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1. Richy F, et al. Structural and symptomatic efficacy of glucosamine and chondroitin in knee osteoarthritis. A comprehensive meta-analysis. Arch Intern Med 2003;163:1514-22.
2. Towheed TE, et al. Glucosamine therapy for treating osteoarthritis. Cochrane Database Syst Rev 2002;Issue 4.
3. Reginster JY, et al. Long-term effects of glucosamine sulphate on osteoarthritis progression: a randomised, placebo-controlled clinical trial. Lancet 2001;357: 251-56.
4. Pavelka K, et al. Glucosamine sulfate use and delay of progression of knee osteoarthritis. Arch Intern Med 2002;162: 2113-23.
5. Tallia AF and Cardone DA. Asthma exacerbation associated with glucosamine-chondroitin supplement. J Am Board Fam Pract 2002;15: 481-4.
6. Matheu V, et al. Immediate-hypersensitivity reaction to glucosamine sulfate. Allergy 1999;54: 643.