What should I know about diagnosing food intolerance?

Food diaries: Keeping a food diary is generally considered a safe and effective way to pinpoint food intolerances. Keeping a food diary prior to a medical appointment may help diagnosis proceed faster, but maintaining adequate nutrition should remain a priority.

Elimination diet: The elimination diet is safe and effective when done under the direction of a medical professional. A qualified healthcare provider can help ensure adequate nutrition while eliminating possible trigger foods.

Hydrogen breath test: During hydrogen breath testing the individual ingests fairly large quantities of the possible trigger substance (i.e. lactose). This may induce symptoms similar to what is experienced during the reaction (abdominal pain, bloating, gas, diarrhea, constipation).

Stool culture: A stool culture is generally considered safe and painless.

Serum analysis: The primary side effects of blood testing are possible discomfort and bruising at the puncture site.

Skin test: Skin tests cause minimal, if any, discomfort. The needles used barely penetrate the skin's surface and will not cause bleeding. Some itching may arise if an allergic response does occur.

Imaging: Endoscopy, sigmoidoscopy, and colonoscopy are generally considered safe procedures; however, as they are somewhat invasive, they do carry a small risk of bleeding, infection, or tearing of the gastrointestinal tract.