The science of nutrition and healthy eating

1.1 Symptoms of a food allergy

The symptoms of a food allergy are often seen in the gastrointestinal tract, skin and respiratory system (Table 1).

Table 1 Common symptoms of a food allergy

Organ affected Symptoms seen
Gastrointestinal system Abdominal pain, vomiting, diarrhoea
Skin Itching, swelling (rash calledurticaria or nettle rash)
Respiratory system Runny nose, sneezing, wheezing, cough

These reactions can occur very quickly, within minutes of eating or even touching the offending food. This is known as an immediate-type reaction. Reactions can even occur days after eating the food, which is called a delayed reaction.

A strong allergic response to the allergen can cause a severe reaction called anaphylaxis. There was a 615% increase in the rate of hospital admissions for anaphylaxis in the UK in the 20 years to 2012 (Turner et al., 2015). Admittedly, this was not just for food-related anaphylaxis, but this increase is worrying and cannot be ignored. Anaphylaxis needs to be treated urgently and we will explore this later.