Glucosamine and Chondroitin

For many years, glucosamine and chondroitin – both separately and combined – have been some of the most commonly used supplements for osteoarthritis (OA). While evidence in the past has been conflicting as to whether they’re effective, research now concludes that they’re not effective for treating OA of the hip or knee.

And in the case of glucosamine, it may have harmful side effects for people with a shellfish allergy or taking certain medicines.

What is osteoarthritis?

At the ends of most of our bones, we have a slippery cushion called cartilage. It absorbs shocks and helps our joints move smoothly. For people with osteoarthritis, this cushiony cartilage becomes brittle and breaks down. Some pieces of cartilage may even break away and float around inside the joint, causing inflammation and pain. The cartilage no longer has a smooth, even surface, so the joint becomes stiff and painful to move.

OA can develop in any joint but most commonly occurs in weight-bearing joints such as the knees and hips.

What is glucosamine?

Glucosamine is a naturally occurring sugar found in our cartilage. One of the roles of glucosamine is to build and repair cartilage.

Glucosamine supplements come in two forms – glucosamine sulfate and glucosamine hydrochloride. They’re typically made from crab, lobster or shrimp shells; however, synthetic forms are also available. Supplements come in tablet or liquid form and are often combined with chondroitin.

What is chondroitin?

Chondroitin is another natural substance found in cartilage. One of its jobs is to help draw water and nutrients into the cartilage, keeping it spongy and healthy (1). Chondroitin supplements are available as chondroitin sulfate. They’re made from cow or shark cartilage and are available in tablet, capsule or powder form.

Treating osteoarthritis

Osteoarthritis is a painful condition, but we don’t currently have a magic pill that can treat it quickly and effectively. Pain-relieving medicines (analgesics) such as paracetamol and anti-inflammatories may temporarily relieve pain and inflammation. But they’re not a cure or long-term treatment.

This explains why, to some extent, glucosamine and chondroitin became so popular when they became available. Many research studies highlighted the benefits of this new, ‘natural’ treatment. The studies seemed to provide evidence that these supplements provided pain relief for many people with osteoarthritis and improved their joint function.

However, as more research has taken place, the evidence for using these supplements has come under more and more scrutiny. The earlier studies that had been the basis for the positive recommendations for using glucosamine and chondroitin were often small and of low quality.

Because of this lack of good quality evidence, peak bodies such as the American College of Rheumatology (2) the Australian Rheumatology Association (3) and the Royal Australian College of General Practitioners (4) recommend against the use of glucosamine and/or chondroitin to treat osteoarthritis of the hip and/or knee.

Safety concerns

Glucosamine supplements are usually made of shellfish, so if you have a shellfish allergy, you shouldn’t use them. Glucosamine can also affect your blood sugar levels and may adversely affect diabetes, cholesterol, chemotherapy and blood-thinning medicines. Before taking glucosamine, talk with your doctor or pharmacist for information.

Evidence-based treatments for osteoarthritis

The good news is that there are other very effective treatments for osteoarthritis, including.

Regular, consistent exercise. It’s one of the best things you can do if you have OA. It’ll help relieve your pain, improve the function of your joints and strengthen the muscles that surround and support your joints. Exercise has many other great health benefits too, such as helping you maintain a healthy weight, get a good night’s sleep and improve your mood. For OA, the best exercises are ones that you enjoy and can commit to doing regularly. This may include walking, strengthening exercises, tai chi, cycling and water exercise. Talk with a physio or exercise physiologist if you need assistance starting a new exercise program or to have an exercise program tailored to your needs.
If you’re overweight or obese, losing weight will also relieve your pain. Losing about 10% of your body weight may decrease your pain by up to 50% when achieved through a combination of diet and exercise.v Talk with your doctor or a dietitian if you need help losing weight.
Mobility aids such as canes or walkers may be helpful for some people with hip and/or knee OA to help them get around safely and reduce pain in their weight-bearing joints.
Heat packs, when applied to a painful joint, can provide temporary pain relief.
Massage may also provide temporary pain relief.

But what if glucosamine and/or chondroitin supplements are working for you?

If you’ve been taking these supplements for some time, you haven’t had any adverse side effects, and you want to continue taking it, talk with your doctor or pharmacist for information and support.