Food intolerance tests: ask what the result actually means

A long list of foods marked red on a test report can feel like an answer. Before changing your meals, ask a more useful question: what condition was this test designed to diagnose, and how does the result fit your symptoms?

IgG panels do not diagnose food intolerance

The Australasian Society of Clinical Immunology and Allergy (ASCIA) states that there is no credible evidence for using food-specific IgG antibody measurements to diagnose food allergy or intolerance. These antibodies can be found in healthy people and can reflect exposure to foods. A positive panel is not, by itself, a reason to stop eating those foods.

Allergy testing answers a different question

When a clinical history suggests food allergy, a doctor may choose targeted skin-prick or food-specific IgE blood tests. Results need medical interpretation: a positive result does not automatically prove that eating the food will cause a reaction. A medically supervised food challenge may sometimes be needed. Do not test a suspected allergen by eating it at home.

Allergy tests are not general screening tools for every cause of bloating or digestive discomfort. Our lactose-free, dairy-free and milk allergy guide explains why these are different questions.

Start with the pattern, then choose the investigation

Bring your GP a clear account of the food, amount, timing and symptoms, including whether the reaction has happened more than once. Take any existing test reports and a list of medicines or supplements. The right investigation depends on the suspected condition; one broad panel cannot answer every digestive question.

A short food and symptom diary can support this discussion. It should help you describe what happened, rather than become a scoring system that labels foods good or bad.

Keep restriction purposeful and temporary

If an elimination trial is appropriate, agree its scope, duration and review plan with your clinician and dietitian. Reintroduction is part of identifying what matters. Long, broad restrictions can compromise nutrition, particularly for children. Keep existing medical allergy precautions in place while seeking advice; an unproven panel is not a reason to stop prescribed treatment or disregard a confirmed diagnosis.

Digestive enzymes also do not diagnose the cause of symptoms or replace food-allergy precautions. Explore our Knowledge Bank alongside personalised advice.

Further reading

ASCIA: evidence-based and unproven testing; ASCIA: food allergy testing; ASCIA: food intolerance.