What to expect from food intolerance testing for lactose intolerance

Your clinician may ask when bloating, cramps, gas or loose stools begin after milk or other dairy foods, and whether yoghurt or hard cheese causes the same response. They may review medicines, bowel symptoms and your usual diet because similar symptoms can have other explanations. Testing may involve a hydrogen breath test after drinking a measured lactose solution. Another approach is removing lactose for a planned period and then reintroducing it while tracking symptoms. The result is interpreted alongside your history, rather than from a test in isolation.

Bring a short food and symptom diary, including the food, portion, timing and symptoms. Do not make major long-term dietary changes before speaking with a clinician unless advised. Ask how to prepare for a breath test, since eating, smoking and some medicines can affect instructions. If lactose is reduced, discuss calcium and vitamin D sources and suitable alternatives so your diet remains balanced. Food intolerance testing can help clarify lactose-related symptoms, but it does not diagnose a milk allergy.

Seek urgent help for swelling of the lips or throat, wheezing, trouble breathing, faintness or a rapidly spreading itchy rash after dairy. These features may suggest an allergic reaction rather than lactose intolerance. Arrange medical review for persistent vomiting, blood in the stool, unexplained weight loss, severe abdominal pain or symptoms that wake you repeatedly at night.

Ask whether your pattern fits lactose intolerance, whether a breath test or dietary trial is more suitable, and how to maintain calcium intake if lactose is reduced. You can also ask when to reintroduce dairy and which symptoms should prompt reassessment.