For over a decade, chondroitin and glucosamine have been recommended in guidelines, prescribed by general practitioners and rheumatologists, and used by patients as over-the-counter medications to modify the clinical and radiological course of arthritis. Nevertheless, a recent meta-analysis in the British Journal of Medicine (BMJ) measuring pain intensity and joint inflammation in over 3,800 patients concludes that chondroitin, glucosamine and their combination do not reduce joint pain or have an impact on narrowing of joint space .
Cartilage is an elastic, fibrous connective tissue found in many areas of the human body, including the joints between bones, the elbow, the knee and the ankle. Glucosamine and chondroitin are key structural components in cartilage and are frequently prescribed to reduce joint pain and slow the progression of the disease. It has been thought that oral administration of these compounds compensates for the loss of cartilage in damaged joints. Glucosamine and chondroitin are partially absorbed in the intestine and several studies suggest that at least some of what was ingested can reach the joints. Nevertheless, the recent study, not a clinical trial itself, but a study of studies (i.e. a meta-analysis), compared glucosamine hydrochloride, glucosamine sulphate, and/or chondroitin with placebos and found that none reduced pain intensity or changed the width of joint space (i.e. reduction of inflammation) .
A study published in The Journal of the American Medical Association (JAMA) made headlines recently. The review, “Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: Systematic review and meta-analysis”, assessed the effect of antioxidant supplementation on mortality in randomized primary and secondary prevention trials and concluded that beta carotene, vitamin A and vitamin E supplementation are positively correlated with death and may increase mortality.