Around 5% of the population have some kind of food allergy. This varies with age, as does the allergen containing food; for example the most common food allergies in babies are eggs and milk yet very few adults are allergic to either.
The severity and sensitivity of these food allergies varies greatly between people. In those who are described as “exquisitely sensitive” only the tiniest amount of the food is sufficient to provoke a reaction. In one case a boy was given a kiss on the cheek by his aunt shortly after she had finished a packet of peanuts. Within minutes the boys face had begun to swell up in an allergic reaction.
Whilst this level of sensitivity is unusual, severe reactions are not. Most people will only experience a mild, local reaction to a food such as tingling and swelling of the lips. However, for a significant minority these reactions can be life-threatening causing anaphylaxis.
In theory any food can cause an allergic reaction, yet it is only eight that are responsible for around 90 percent of food related allergic reactions – the so-called “Big 8“. These are: