What to expect from food intolerance testing for IBS

IBS is assessed from a pattern of abdominal pain linked with bowel habit changes after other conditions have been considered. A clinician may ask about dairy, wheat, caffeine, spicy foods, sweeteners, and meal timing. Tests are chosen for your symptoms; some commercial panels do not reliably explain IBS symptoms.

Depending on your history, assessment may include blood tests or tests for conditions such as coeliac disease or lactose intolerance. A food diary records what you ate, the timing of symptoms, stool changes, and other influences such as stress or illness.

Keep eating a varied diet unless a clinician advises otherwise, and do not remove gluten before coeliac testing without discussing it because this can affect results. Bring your medicine list and diary to the appointment.

If an elimination trial is suggested, change one planned group at a time and arrange review. A dietitian can help protect fibre, fluid, and nutrient intake, then guide reintroduction so unnecessary long-term restriction is avoided.

Seek prompt medical care for blood in the stool, black stools, unexplained weight loss, persistent vomiting, fever, severe or worsening pain, abdominal swelling, or inability to pass stool or gas. Do not assume these features are food intolerance or IBS.

Ask which diagnosis you are checking for, which tests are appropriate, whether you should continue eating gluten before testing, how long to trial a food change, and how to maintain nutrition during it.