Allergies are more common nowadays than ever before. The reasons for the explosion in allergy over the last 50 years are still not really known. Some scientists think that it is related to a reduction in infections (the hygiene hypothesis), our diets and pollution may also play a role. Some families are more prone to allergies than others and it is clear that our genes are also involved.
Allergies are caused by over activity of the immune system called hypersensitivity. The immune system is designed to recognise and fight off invading germs, viruses and other micro-organisms. Allergies are caused when the immune system recognises environmental and food triggers instead of germs. Common causes are dust, pet fur, pollens and food. Substances that cause allergy are known as allergens.
Our immune systems recognise foreign invaders through white blood cells and antibodies. Allergens are recognised by a particular type of antibody known as Immunoglobulin E – often shortened to IgE – known as the “allergy antibody”.
IgE can be detected by skin prick testing used in the Allergy Healthcare clinic.