How summer affects your health… for good or ill

There are old wives’ tales about how the cold and damp make arthritis worse, but there’s no scientific evidence to suggest that’s the case, says Jo Cumming, helpline manager of Arthritis Care.

In fact, sufferers have to take extra care at this time of year, because many of the most common medications for the condition make their skin extra sensitive to the sun.

Common culprits are non-steroidal anti inflammatory drugs (NSAIDs) such as dicolfenac, fetoprotein and indomethacin. Even over-the-counter remedies like ibuprofen can cause light sensitivity.  Even just a little exposure to the sun can cause rashes and rapid burning of any exposed skin.

Bumps, blistering, pigment changes and even skin crusting can also be a problem, so anyone taking such medication should use high SPF sun cream and avoid spending too long in the sun.  Because of this, blood sugar levels must be monitored more closely to avoid a life-threatening hypoglycaemic attack caused when glucose levels fall too low.

Caroline Butler, care adviser for Diabetes UK, says: ‘Because of the increased absorption of insulin, patients should wear sunscreen and avoid spending too much time out in the sun.  ‘And because insulin is absorbed more quickly in hot weather, they must do more tests to discover if they have low glucose levels and take supplements like Lucozade or sugary sweets if they do.’

Experts recommend sufferers measure their blood insulin levels when they wake up, go to bed and two hours after every meal. Men’s sperm count is lower in summer than winter, with couples least likely to conceive in July and August.

Experts believe low sperm counts are a throwback to when life was tougher: babies conceived in summer were born when food was scarce, whereas winter-conceived children came into the world at the same time as the harvest. Men’s bodies evolved to maximise chances of an autumn birth.

New research also suggests summer reduces a woman’s ability to conceive. An Italian study discovered women’s bodies produce extra melatonin in winter, which makes the eggs bigger and easier for the sperm to penetrate.

The womb lining also thickens in winter, making it more likely an embryo will implant successfully. These factors mean even IVF is more successful during winter. While more people suffer from pneumonia – an inflammation of the lungs – in winter, attacks in summer can be more severe.

This is because people tend not to drink enough water and dehydration thickens bronchial secretions in the lungs – which, when already inflamed by pneumonia, makes breathing even more difficult.  Professor Stephen Spiro of the British Lung Foundation says: ‘The thickened sputum becomes harder to cough up and so sits around in the lungs, making a good culture medium for bugs.’

Most at risk are the over-65s and people with chronic illnesses such as kidney and heart disease. Professor Spiro recommends that everyone of every age should drink at least two litres of water every day during summer to protect their lung function.