Breathe easy

Thirty years ago asthma was a rare and frightening condition. Today some 5.1 million people have been diagnosed as suffering from the condition: that's one in 13 adults and one in eight children. Yet this chronic disorder - in which inflammation of the airways, often triggered by an allergic reaction, leads to coughing, breathlessness and a characteristic wheeze - can still be life-threatening.

'It has increased a lot in the past three decades, especially among children,' says Caroline Moye of the UK's National Asthma Campaign. 'But people don't always realise that it can also strike adults, even in their 40s or 50s, who have never had an asthma attack before.'

The cost of comfort?
Why is it increasing? According to some experts, we can blame our modern western taste for cleanliness and vaccinations. Challenged by so few germs, the immune system never learns to fight infections and instead creates allergies by turning against minor nuisances such as dust or cat fur.

Other researchers blame fitted carpets and central heating for nourishing huge populations of chest-irritating dust mites. Certainly asthma has increased most sharply in the comfortable homes of Western Europe and North America.

'We don't know what causes asthma,' admits Ms Moye, whose organisation puts £2 million a year into trying to find out why people get asthma, and stop it happening. 'Some people inherit it, we know. And there's research going on into lifestyle, environment and diet. Studies are coming out all the time stating that "genes are very important" or "diet is very important."'