Knuckle-cracking is fine – and bad weather doesn’t make arthritis worse: nine myths about your joints busted | Health & wellbeing

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Cracking your knuckles is bad …

It might get on other people’s nerves, but clicking your knuckles probably won’t exacerbate joint problems or increase the chances of arthritis. The joints are lubricated by synovial fluid, which contains dissolved nitrogen gas.

When you stretch a joint, the cavity containing this fluid expands, causing a pressure drop. This causes the dissolved gas to come out of the solution and form a bubble – and the rapid release of the gas creates a popping sound.

The same knuckle can’t be cracked again straight away because it takes around 20 minutes before the bubbles dissolve back in to the fluid. Several studies suggest the habit is harmless, including one from a California doctor who spent decades regularly cracking the knuckles on only one hand: an X-ray found no difference in the arthritis between both his hands. Another study of a group of 300 patients found no link between a history of joint-cracking and arthritis.

Gas bubbles around the joints can also cause joints to make clicking sounds during exercise, although repeated popping or clicking noises can also be caused by tendons or ligaments moving over bony prominences beneath the joint.

Rheumatoid arthritis and osteoarthritis are the same …

Arthritis means “inflammation of the joint”, but the inflammation can be triggered by different causes. Osteoarthritis is caused by wear and tear and normally affects just one joint, most often the knee or hip, and is most common in over-50s. People whose job involves heavy manual labour, such as bricklaying, or requires a lot of kneeling, such as carpentry, are at a higher risk. Obesity, which also puts more strain on the joints, is another major risk factor. But there is also a genetic component, with research putting the heritability at 40%-70%.

Rheumatoid arthritis is an autoimmune condition where the immune system goes rogue and attacks the synovial membrane that encases and protects the joints. It is less common than osteoarthritis, most often starts in middle age and causes pain in joints throughout the body. Women are two to three times more likely to have it than men. There are certain genes that make rheumatoid arthritis more likely and symptoms more severe, but smoking and obesity also ramp up the risk.

There is nothing you can do to prevent arthritis …

For osteoarthritis, being overweight is a significant risk factor as it puts more strain on the joints, so maintaining a healthy weight helps mitigate risk. For rheumatoid arthritis, smoking is one of the biggest risk factors – and being a current smoker has been shown to exacerbate symptoms. So quitting smoking helps reduce the risk.

Joint pain during the menopause is inevitable …

Oestrogen helps to maintain cartilage and other joint tissues, meaning that joints are sensitive to levels of the hormone in the body. As oestrogen falls during menopause, many women experience joint pain. Hormone-replacement therapy (HRT) is widely accepted as the most effective treatment for menopause symptoms, including joint pain, and works by restoring oestrogen levels; but HRT is not always suitable and some women may prefer other ways of managing symptoms. A major way to improve joint pain is through exercise. Weight-bearing exercise that strengthens the musculoskeletal system is particularly good for alleviating joint aches. This could include walking or running, for the lower body, or doing weights in the gym, for the upper body.

Collagen supplements can help to rebuild joints …

Collagen is the most abundant protein in the body and plays a vital role in forming connective tissue. Without enough collagen, our skin, bones, muscles, tendons and cartilage lose elasticity and strength. The body makes less collagen as we age, and so there is some logic to taking supplements to make up the deficit, but hard evidence that this makes a meaningful difference is lacking. Some studies have found encouraging results, but most have been small and funded by companies that make the supplements, increasing the potential for bias.

Supplements are unnecessary to maintain healthy joints …

It should be possible for most people to get most of the vitamins and minerals required for healthy bones from a healthy diet. But vitamin D is the exception. Vitamin D helps the body absorb calcium, which is essential for building bone mass. It is made in the skin during exposure to sunlight and during summer months this source is normally sufficient. However, during winter it isn’t possible to make enough vitamin D through sun exposure alone and it can be hard to make up the deficit purely through dietary sources such as oily fish, meat and eggs. In the UK, the NHS says adults should consider taking supplements in the winter months. Vitamin D deficiency has been linked to joint pain and it is also a common cause of rickets, from which the bones soften and deform.

Ray of sunshine … adults should consider vitamin D supplements during the winter months. Photograph: Brian Hagiwara/Getty Images

Your diet doesn’t affect your joints …

Inflammation is often a cause of joint pain and stiffness, so following a diet that reduces inflammation could help. There is no single magic ingredient, but avoiding too much red meat, processed food and sugar and ensuring your diet includes omega-3 fatty acids and vitamins is a good place to start.

Gout is no longer a health concern …

Gout is associated with portly, ruddy-faced middle-aged men who overindulge in rich food and alcohol – Henry VIII was a sufferer. But gout is increasingly affecting younger people and women, with research showing a global increase in the number of people aged 15-39 being diagnosed, from 39 cases per 100,000 people in 1990 to 46 per 100,000 in 2019. The trend is believed to be driven by the steep rise in obesity and diabetes, which are risk factors.

Gout is a type of arthritis that causes sudden, severe joint pain and inflammation, often in the big toe. It is caused by high levels of uric acid building up in the blood, which can lead to needle-shaped crystals forming around the joints. Uric acid is a by-product of purines, which are found in higher levels in red meats, shellfish and alcoholic drinks. Pre-menopause, women are at much lower risk of gout because oestrogen increases the removal of uric acid by the kidneys. Being overweight, having type 2 diabetes, high cholesterol or high blood pressure are all risk factors, and this is thought to be driving the increase in younger people affected by gout.

Rain and thunderstorms make arthritis worse …

You might know someone who claims they can predict bad weather by a flare-up in arthritis pain. And some have suggested that the purported link could be due to the drop in atmospheric pressure that often precedes bad weather causing joints to expand. However, there is little conclusive evidence to support this idea. One study, based on data from more than 11 million medical visits by US patients, found no pattern linking rainy days to more aches and pains – in fact, people were slightly more likely to seek treatment on dry days.