Different Test Methods for Food Allergy and Intolerance

For many people suffering with symptoms of food intolerance or allergy, the search for a solution leads to the exploration of a variety of tests…  but not all tests are created equal. A quick google search for IgG, or food intolerance, testing will reveal a wide range of tests available: differing in price, foods covered, comprehensiveness and reporting. Here we look at a few different methods and how they work.

Hair Mineral Analysis Test (HMAT)

There are several companies offering food sensitivity testing on samples of hair, being a non invasive alternative to blood testing. At first glance these tests appear to be quite cheap in comparison to other test methods however there is no evidence that hair testing can detect IgG food allergy (commonly known as food intolerance) and several studies confirm that results are unreliable. Hair testing can be an excellent method for determining vitamin/mineral deficiency and heavy metal toxicity, however the hair sample is easily affected by environmental toxins, hair dye, shampoos and other hair products, and is therefore not the most reliable way to test for IgG mediated food allergy.

Breath test

A hydrogen breath test is often used as a diagnostic tool for people with irritable bowel syndrome to determine whether lactose intolerance or fructose malabsorption is present.  These kinds of issues are related to sugars and occur when there is an enzyme deficiency in the body.  While the hydrogen breath test is the only way to detect lactose or fructose intolerance, it does not detect IgG food allergy.  If a breath test has been conducted, and lactose or fructose intolerance ruled out, you might like to then look into IgG testing to determine if an IgG mediated allergy is present.

Skin-prick or ‘scratch’ test

Skin-prick or scratch tests involve a Doctor or practitioner placing various allergens on an area of the patient’s skin to determine if there is a reaction. While quite invasive, the skin-prick or scratch test, is accurate only for IgE mediated allergies (traditional allergic reactions) – this method cannot identify IgG food allergy.

Elimination diets

An elimination diet is the traditional way to determine if a person has a food intolerance. The patient is instructed by their practitioner to cut out most foods from their diet, allowing just plain foods during the elimination phase, and then ‘challenging’ themselves with other foods to determine if there is a reaction. This can be a long-winded, frustrating and nutritionally deficient time for the patient.

Blood test

A blood test would be one of the more common ways to test for intolerance against foods, but there are many different blood tests available – some more accurate than others.  An ELISA-based blood serum test is stable, reliable and completely reproducible.  Other blood testing methods including blood spot, whole blood or cytotoxic testing, can be unreliable due to morphological changes taking place within the sample if it is not tested within a certain time-frame and some blood test methods can also be affected by drugs or medication. It is important to do your research and make an educated decision on which test method is best for you.