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What is a food allergy?

In a food allergy the immune system sees a harmless protein (in milk, peanut, egg) as an intruder and makes antibodies against it. The next time you eat it, the body reacts: often within minutes, sometimes after a few hours. An intolerance is different: an enzyme is missing or the gut reacts, without the immune system taking part.

Short of breath, a swelling tongue or throat, or dizzy after eating? Use the adrenaline auto-injector if one has been prescribed and call 112 straight away. Even if it then seems to get better.

What a food allergy is and how it differs from an intolerance

Symptoms: itching or tingling in the mouth, swelling of lips, tongue or throat, hives, vomiting or diarrhoea, breathing difficulty. In a severe reaction (anaphylaxis) blood pressure drops and breathing becomes hard: call 112.
A doctor makes the diagnosis with a skin or blood test and, if needed, a challenge test. Cutting out an allergen yourself without a diagnosis can cause deficiencies and makes later tests unreliable.
Fourteen allergens are so common and so serious in the EU that they must be in bold on every label. This site knows all fourteen, plus the hundreds of specific species and substances manufacturers list besides.

What to do after the diagnosis

Always carry the adrenaline auto-injector if one has been prescribed, and make sure people around you know how it works.
Read the label with every purchase, also of products you have bought for years: recipes change. This site tracks those changes, but the pack decides.
Always discuss a diet with a dietitian: anyone cutting out milk or gluten needs to know where the replacement nutrients come from.

What this site does and does not do

We read the ingredient list and the allergen declaration as the supermarket publishes them, and hide every product that contains the allergen. Products without allergen information are hidden by default too: unknown is not the same as safe. What we cannot do is read the pack in the shop. Recipes change, and the information here can lag behind. When in doubt the label in your hand decides, and for questions about your health your doctor or dietitian.

More guides

E numbersWhat the numbers mean, and how to find a product without a given E number.Palm oilWhere palm oil is, and the names it goes by on the label.SugarSugar-free, low-sugar or no added sugar: three claims, three meanings.VeganRecognising animal ingredients, also when they hide behind an E number.Reading the labelBold, the order and the pitfalls: reading a label in ten seconds.May contain tracesWhat the warning does and does not say, and when to take it seriously.AnaphylaxisRecognising a severe allergic reaction, and what to do then.

Per allergen — milk, gluten, nuts, peanut and the rest.

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