Food allergy can be easy to recognise as reactions will generally occur within minutes or hours after the food is ingested.The most common food allergens are cow's milk, egg, wheat, peanuts, seafood and possibly soybeans.

Common food allergy tests can include:

  • Skin prick tests:  A small and diluted amount of the possible food allergen is put on your skin and a very small, fine scratch is made through it. If your skin becomes red and swollen around the scratch, your test is positive for that particular food.
  • Blood tests: These are called RAST tests and can measure the amount of antibodies in your blood to a suspected food allergen. You may have a blood test if you can’t have a skin prick test for some reason, for example, if you have severe eczema.
  • Elimination diets: This is when you stop eating the food or foods that may be causing your allergic reaction to see whether your symptoms get better. If they do, you then start eating the suspected food again to see if your symptoms come back. If they do, it’s likely that you’re allergic to that food.
  • Food challenges: If you have a severe food allergy, you will be given a small amount of the food which may be causing your allergic reaction, to see what happens. You should only have this type of test done in a hospital or clinic, where you can be treated quickly if you do have a severe reaction.