What is Glucosamine?
Glucosamine (gloo kose’ a meen) is a natural component of cartilage that is a widely used as an over-the-counter nutritional supplement purported to decrease the pain and cartilage loss of osteoarthritis. Glucosamine is commonly taken in combination with chondroitin (kon droe’ i tin), which is a glycosaminoglycan that is also present in cartilage. Glucosamine is an amino sugar and a prominent molecule in the biochemical pathways of synthesis of glycosylated proteins and lipids. It is also a major component of keratin sulfate and hyaluronic acid which are present in articular cartilage and synovial fluid. Both glucosamine and chondroitin are reduced in osteoarthritis. Glucosamine is commercially available alone and in combination with chondroitin and widely used for osteoarthritis and arthritic pain. Glucosamine is typically taken in doses of 500 mg three times daily and chondroitin sulfate in doses of 200 to 400 mg three times daily.
A study was conducted to measure the effect of glucosamine supplementation on people experiencing regular knee pain by Braham R1, Dawson B, Goodman C. The results suggest that glucosamine supplementation can provide some degree of pain relief and improved function in persons who experience regular knee pain, which may be caused by prior cartilage injury and/or osteoarthritis. The trends in the results also suggest that, at a dosage of 2,000 mg per day, the majority of improvements are present after eight weeks.
“Results from several well-designed scientific studies suggest that glucosamine supplements may work for OA, particularly OA of the knee or hip. In general, these studies suggest that glucosamine reduces pain, improves function in people with hip or knee OA, reduces joint swelling and stiffness, and provides relief from OA symptoms for up to 3 months after treatment is stopped.”
“Side effects are uncommon and mild and may include abdominal discomfort, nausea, fatigue and headache; but in placebo controlled trials, side effects during glucosamine therapy were no more frequent than with receipt of placebo.”
Glucosamine (C6H13NO5) is an amino sugar and a prominent precursor in the biochemical synthesis of glycosylated proteins and lipids. Glucosamine is part of the structure of the polysaccharides chitosan and chitin, which compose the exoskeletons of crustaceans and other arthropods, as well as the cell walls of fungi and many higher organisms. Glucosamine is one of the most abundant monosaccharides. It is produced commercially by the hydrolysis of crustacean exoskeletons or, less commonly, by fermentation of a grain such as corn or wheat.
The effectiveness of glucosamine has not been scientifically established for any condition, and the supplement has been shown to cause harm in high doses. Despite this, in the US it is one of the most common non-vitamin, non-mineral, dietary supplements used by adults.