Allergies are very common. According to the British Allergy Foundation, one in three people in the UK suffer from an allergy at some time in their lives. The numbers are increasing every year and as many as half of those affected are children.
The reason for the rise is unclear. Some experts believe it is associated with pollution. Another theory is that allergies are caused by living in a cleaner, germ-free environment, which reduces the number of germs our immune system has to deal with. This causes it to overreact when it comes into contact with harmless substances.