One of the best known non-drug treatments for joint pain is glucosamine, an essential part of the building material for joints and the cellular ‘glue’ that holds the entire body together. It is a naturally occurring amino sugar (a molecule combining an amino acid with a simple sugar) and found in almost all the tissues of your body, although joint cartilage contains a higher concentration of glucosamine than any other structural tissue. It is used to make N-acetylglucosamine which, in turn, is one of the building blocks for the making of cartilage.
Daily wear and tear on our joints means that the connective tissue that surrounds them (cartilage, tendons, and ligaments) requires constant renewal, needing an ongoing supply of glucosamine. Unfortunately, it appears that some people are less able to make glucosamine as they get older. When this rebuilding process slows down, the result is degenerative joint diseases such as arthritis.
The mechanism by which glucosamine appears to stop or reverse joint degeneration is by providing the body with the materials needed to build and repair cartilage. It plays a fundamental role in the formation of joints, tendons, ligaments, synovial fluid, bone and many more body parts, including skin and blood vessels. Cartilage in joints consists of cells embedded in collagen that sits within a framework of watery ‘proteoglycan’ gel – it is the integrity of this structure that allows joints to remain flexible and able to resist the pressure of impact and gravity. So glucosamine appears to stop or reverse joint degeneration by providing the body with the materials it needs to form these proteoglycans (the framework for joint structure) and may prevent their breakdown in the body.There is also some evidence that glucosamine helps the incorporation of sulphur into cartilage – sulphur is an essential nutrient for keeping all connective tissue stable.
Although the body can make glucosamine, if you’ve got damaged joints you are unlikely to make enough – unless you are in the habit of munching on sea shells, which is the richest dietary source. Taking a substantial quantity of glucosamine as a nutritional supplement has been shown to slow down or even reverse this degenerative process. There are about 440,000 joint replacements every year in the US, and many could be avoided with the right nutrition. But how does glucosamine do the job?
Glucosamine appears to be particularly effective in protecting and strengthening the cartilage around your knees, hips, spine and hands. And while it can do little to actually restore cartilage that has completely worn away, it helps to prevent further joint damage and appears to slow the development of mild to moderate osteoarthritis. As mentioned earlier, traditional NSAIDs prescribed for arthritis actually impair your body’s cartilage-building capacity.
A 2001 study in The Lancet reported that glucosamine actually slowed the progression of osteoarthritis of the knee. Over the course of three years, they measured spaces between the patients’ joints and tracked their symptoms. Those on glucosamine showed no further narrowing of joints in the knee, which is an indicator of thinning cartilage. Put another way, glucosamine appeared to protect the shock-absorbing cartilage that cushions the bones. In contrast, the condition of the patients taking the placebo steadily worsened.
Because glucosamine helps to reinforce the cartilage around your joints, it may hasten the healing of acute joint injuries such as sprained ankles or fingers, and of muscle injuries such as strains. In strengthening joints, glucosamine also helps to prevent future injury.
Back pain control
Glucosamine strengthens the tissues supporting the spinal discs that line the back. It may therefore improve back pain resulting from either muscle strain or arthritis, and speed the healing of strained back muscles. Glucosamine seems to have similar effects on pain in the upper spine and neck.
As your body ages, the cartilage supporting and cushioning all of your joints tends to wear down. By protecting and strengthening your cartilage, glucosamine may help to postpone this process and reduce the risk of osteoarthritis.
In addition, most studies indicate that arthritis sufferers can move more freely and report increased overall mobility after taking glucosamine. In addition, several studies have shown that glucosamine can be as effective as NSAIDS for easing arthritic pain and inflammation, and there are less of the stomach-irritating side effects associated with NSAIDs.
Overall, the evidence for glucosamine is good. So good, in fact, the pharmaceutical industry have attempted to get it reclassified as a medicine and not a food.
A study in China of people with osteoarthritis of the knee found that participants taking 1500mg of glucosamine sulphate daily had a similar reduction in symptoms to those taking the NSAID ibuprofen, 1200mg daily. However, the glucosamine group tolerated their medicine much better. Another study compared the effects of glucosamine with ibuprofen painkillers. While the participants on the ibuprofen initially had a more dramatic reduction in pain, it stabilised after four weeks, whereas those on the glucosamine reported less pain after four and also after eight weeks.
And in four high-quality 2005 studies that gave glucosamine sulphate versus NSAIDs, the glucosamine worked better in two, and was equivalent to the NSAIDs in the other two, again without the side effects.
Another study from the University of Siena, Italy evaluated the effect of 1,500mg glucosamine on its own versus placebo for 12 weeks in 60 patients with knee arthritis. Pain at rest and on moving improved significantly more in the glucosamine group than the placebo group, by 40 per cent and 16 per cent, respectively. Improvements continued for eight weeks after supplementation was stopped, but returned to baseline after another four weeks. You have to keep taking it.
Not all placebo controlled trials, however, have proven effective. Two earlier trials found significant reductions, almost a halving in pain, in both the glucosamine and placebo groups. So it does suggest there’s quite a remarkable ‘placebo’ effect if you’re taking something you think works. That’s why I prefer studies that measure biological inflammatory markers and physical measures of joint function, for example knee flexibility.
Most of the research has been done using glucosamine sulphate, but glucosamine hydrochloride is also known to inhibit Cox-2, which means it has an anti-inflammatory effect. A study in 2018 from Brazil compared the effect of different types of glucosamine: 1,500mg glucosamine sulfate plus 1,200mg chondroitin versus 1,500mg glucosamine hydrochloride plus 1,200mg chondroitin. 100 patients with knee arthritis took either combination for 12 weeks. Pain intensity reduced by 36% in the glucosamine sulfate group and by 44% in the glucosamine hydrochloride group but this difference wasn’t statistically significant.
My advice is to aim for 500 to 1,500mg a day (the usual dosage for glucosamine in trials on its own is 500mg, three times daily). Bear in mind that trials weight there design to maximise the effect while, if you are also changing your diet and introducing other joint friendly nutrients you might not need such a hefty dose.
Many people find that the longer they use it, the more beneficial it feels. It works especially well when combined with MSM.
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