You can’t walk past a chemist these days without seeing displays full of glucosamine, a supposed wonder supplement that purports to provide relief from osteoarthritis.
Osteoarthritis is the most common form of arthritis and occurs when cartilage that cushions the ends of joints loses its elasticity and wears away. The pain, swelling and loss of movement that result can be severe.
Glucosamine is a type of sugar that the body produces naturally. The glucosamine found in supplements, however, is largely derived from the hydrolysis of crustacean exoskeletons – in other words it’s extracted from the shells of crabs, shellfish, shrimp etc. A smaller amount is processed from vegetarian sources like maize, corn and wheat.
Human glucosamine is unstable outside the body, so supplement glucosamine is sold in the more stable forms of glucosamine hydrochloride and glucosamine sulphate.
Joints rely on water-holding substances called glycosaminoglycans. Glycosaminoglycans are found both in the hard cartilage on the ends of bones and in the synovial fluid that separates the articular surfaces within a joint. Their ability to hold many times their weight in water is what gives cartilage and synovial fluid their cushioning effect, allowing the joint ends to move smoothly against each other and the joint itself to absorb impact.
As osteoarthritis progresses, the hard cartilage decays and loses its cushioning ability. Similarly, joint narrowing occurs i.e. the space between the joint ends becomes smaller and contains less of the other cushioning component, synovial fluid.
Glucosamine is a precursor for glycosaminoglycans – the body uses it to produce the water-holding components of cartilage and synovial fluid. The idea behind glucosamine supplements is that they provide the body with the raw material it needs to keep cartilage and synovial fluid healthy and plumped up with water.
Does it Work?
Many people swear by glucosamine supplements, citing reduced pain, greater joint endurance and improved range of movement. Scientific proof of the efficacy of taking oral glucosamine, however, appears inconclusive at present.
Studies run by Rottapharm, a company which produces glucosamine, show clear benefits. Many other studies, though, including a large study sponsored by the US government, conclude that glucosamine supplements give no greater pain relief than a placebo.
Given the conflicting results, it seems that the judgement of whether glucosamine actually provides any relief must be left to the individual. In effect, you have to take it and see.
If you are interested in seeing if it works for you, choose glucosamine sulphate over glucosamine hydrochloride (it seems to be more effective in trials), take around 1500mg per day, and allow 4 – 6 weeks for it to take effect.
Although studies may conflict over the efficacy of glucosamine, they are generally in agreement that the supplements are safe for most people. There are some instances that require caution, however.
As glucosamine is primarily sourced from the exoskeletons of crustaceans, people with seafood allergies may wish to avoid it or ensure they are using a vegetarian version. Diabetics, too, should consult their doctor before taking the supplements. Glucosamine is an amino sugar and it has been suggested that it may contribute to insulin resistance.
Despite the inconclusive results of scientific trials, the relative safety of glucosamine for the general population may make it a supplement worth trying for those suffering from osteoarthritis and other joint problems. You can always throw those pills away if they don’t work for you.
For another view on glucosamine check out this video.