Clinical studies continue on glucosamine sulfate and other forms of possible glucosamine supplements. A review of research on file with the National Library of Medicine and the National Center for Biotechnology Information revealed over 13,500 clinical studies involving either glucosamine sulfate or some other form of glucosamine. These studies include random double-blind clinical trials, reviews, and research on humans and animals. Many questions remain about glucosamine. Researchers want to know how it works, and how it can be best used to treat and prevent disease. However, one thing is abundantly clear: glucosamine sulfate is a safe and effective supplement that can make a difference in the lives of those who use it.

In perhaps the largest and longest study glucosamine to date, 212 patients with mild to moderate osteoarthritis of the knee who were randomly assigned to receive, in double-blind fashion, 1,500 mg of glucosamine sulfate (GS) or placebo once daily for 3 years. The results showed persistent improvement of symptoms and a surprising reduction in joint-space narrowing. "Thus, GS appears to be disease modifying antiarthritic compound, rather than one that merely suppresses symptoms."[15]

This report should alleviate any skepticism or fears about the use of glucosamine as a treatment for arthritis. Writing in an editorial that accompanied the report when it first appeared in the prestigious medical journal Lancet, Tim McAlindon, from the Arthritis Center, Boston University Medical Center, wrote: "Although health-care professionals generally expect to be involved in medical decisions...they are not regarded as a repository of objective advice about nutritional products and are generally kept out of the loop. This situation must change. It is time for the profession to accommodate the possibility that many nutritional products may have valuable therapeutic effects and to regain the credibility of the public at large."[16]