Although a healthy diet is the key component of my advice to anyone suffering from arthritis, there is one dietary supplement which I rate as having a very special role in combating joint problems glucosamine because the evidence is, as I said in my recent article in the Healthspan magazine overwhelming. Nevertheless, not sufficiently overwhelming to convince the regulators, it seems. So, I am pleased to report that further scientific support for this supplement in combination with chondroitin has emerged from the prestigious American GAIT (Glucosamine/ chondroitin Arthritis Intervention Trial) study.

WHAT DO WE KNOW ALREADY?

Osteoarthritis (OA) is the most common joint problem suffered by millions in the Western world; it commonly affects knees, hips, spine or hands. The signs and symptoms are well known: pain, stiffness and decreased mobility. In the past, OA was considered irreversible due to progressive wearing-out of the joint but new research is changing our thinking. We now know that, at least in the early stages of OA, the cartilage cells in the joint are very active, with repair mechanisms operating against destructive breakdown. These repair mechanisms could account for reports of people in whom OA has halted or even reversed,1 once thought to be impossible.

By June 2001, enough evidence had accumulated from over 1,000 subjects taking part in clinical trials for the erstwhile conservative American Arthritis Foundation to issue a statement declaring glucosamine to be an appropriate treatment for osteoarthritis. Even then, scepticism prevailed among some health professionals because a handful of studies showed no benefit, despite most studies showing positive results for the supplement. Contradictory evidence emerging from different human studies on nutritional or herbal interventions is a quandary that we often face in natural medicine. Lack of effect (and so-called negative studies) usually occurs in clinical trials because wrong choices are made about dosage (often too low) or duration of treatment (often too short).

Unlike modern medicine, where therapeutic effects are usually rapid, natural medicine works slowly because its action is totally different. Both nutrition and herbal medicine work to promote the normal functioning of cells and that takes time. Nevertheless, in the long term, by working with and supporting the bodys own healing powers, natural strategies, such as taking glucosamine2 c an be much more effective than modern drugs in reversing damage to cells and tissues. "Glucosamine and chondroitin was more effective than Celebrex in reducing pain. Progression of OA was not only halted, but reversed."

As far as chondroitin is concerned, the development of its evidence-base for efficacy in treating OA has lagged behind that of glucosamine. For many years scientists were sceptical that it could work at all its molecules are so big that some doubted whether they could be absorbed. However, in 1995, researchers demonstrated that small amounts could reach the bloodstream as the intact molecule.3 Since that time, several small but well-designed double-blind clinical studies have shown positive benefits of chondroitin supplementation for the alleviation of knee arthritis compared with placebo treatment.

GAIT

In an attempt to resolve the controversies regarding the effectiveness of glucosamine and chondroitin once and for all, the National Institutes of Health in the USA decided to invest large amounts of public funds in the GAIT study the largest on these supplements ever undertaken. The trial involves thirteen research centres across the United States and is co-ordinated by the University of Utah in Salt Lake City. The work is ongoing, but results of the first phase were reported in November at a conference in San Diego. They showed a positive effect of glucosamine in combination with chrondroitin for treatment of OA of the knee and strongly supported the previous positive outcomes for these supplements.

At the start of the GAIT study, about 1,500 volunteers were randomly assigned to take, on a daily basis for six months, either (1) 1,500 mg of glucosamine, (2) 1,200 mg of chondroitin, (3) a combination of both, (4) an orthodox painkiller called Celebrex, or (5) a placebo. Patients were included in the trial only if they had had knee pain for at least six months before the trial began and showed arthritic changes of the knee under X-ray. Because they were anticipating an improvement in knee health after taking the dietary supplements, the GAIT research team made sure that no one was included if he or she had been taking either glucosamine in the previous three months or chondroitin in the previous six. Success in the trial was measured by a 20 per cent improvement from baseline in the wellestablished WOMAC pain score after six months of treatment (WOMAC stands for the Western Ontario and McMaster Universities Osteoarthritis Index and is recognised by researchers as a sensitive measure of joint health).

The GAIT researchers are using it in two phases: the main, short-term study of six months and a longer-term one. In the latter, half the volunteers will continue their treatments for a further 18 months to ascertain whether glucosamine and chondroitin really do support joint-repair mechanisms and can halt the progression of this debilitating disease. The volunteers who benefited most in the GAIT study had the highest knee pain scores at the beginning. For this subgroup, it was found that glucosamine plus chondroitin was more effective than Celebrex in reducing pain. However, for people with mild knee pain, only Celebrex showed a significant improvement compared to the placebo. The authors suggested that the reason why the combined supplement was found more effective for greater initial pain may be because those suffering from milder forms had more difficulty in accurately assessing changes in their condition.

CONCLUSIONS

While orthodox medication for OA with NSAIDs (non-steroidal antiinflammatory drugs) reduces pain, it does nothing to enhance joint-repair mechanisms and reverse the degeneration process. This contrasts with what has been reported to happen to OA patients receiving natural treatments, including those taking glucosamine and chondroitin. Not only was the progression of the disease halted, but it was reversed. It is hoped the second phase of the GAIT study to be completed in two years time will provide scientific support to underpin these clinical observations.