Food Intolerance Testing

'Food intolerance' (more correctly called non-allergic hypersensitivity) can have a number of different causes such as low levels of digestive enzymes, or heightened sensitivity to natural substances present in foods (such as caffeine, salicylates or histamine). The variation in the cause of food intolerance from person-to-person means that there is no one test to identify all types of food intolerance. Elimination and challenge diets, carried out under the supervision of a suitable qualified person, are the most accurate test.

In recent years, research has shown that measuring the levels of an antibody in the blood (IgG, which is different from the 'allergy' antibody IgE), and using the results to decide which foods to avoid in an elimination diet, can improve the symptoms of people suffering from symptoms such as migraine, IBS and arthritis, which are sometimes linked to food reactions. There is controversy about the role of IgG; it may be present in the blood as a 'marker' for the foods we eat most often, rather than actually being involved in the food intolerance reaction. Nevertheless, some people find the test helps them decide which foods to avoid.

Note that IgG tests are not tests for true food allergy.