What are Food Sensitivity Tests and How Accurate Are They?

If you struggle with digestive issues, like gas or bloating, you may be wondering if something you’re eating is to blame. At-home health testing kits have become increasingly popular and food sensitivity tests are marketed to individuals looking for insight into how their diets are impacting their bodies.

There’s no denying the appeal of at-home testing. It seems easier and more convenient than scheduling a doctor’s office visit and results are often accessible by cell phone or computer within 1 to 2 weeks. But how accurate are the results and is a food sensitivity test really the best option to pinpoint the root cause of your issues?

In this article, we’ll break down everything you need to know about food sensitivity testing.

What are food sensitivity tests?

Food sensitivity tests are designed to analyze how your body reacts to certain foods to help you pinpoint what may be contributing to digestive troubles and other health issues like headaches, brain fog, and acne. 

Unlike a food allergy, food sensitivities do not cause life-threatening symptoms and may not present immediate symptoms. Food sensitivities also differ from food intolerances, which are an inability to digest certain foods. Food sensitivity tests do not test for food allergies or intolerances.

Symptoms of a food sensitivity are often dependent on how much of a given food you eat and may include:

  • Abdominal pain

  • Bloating

  • Constipation

  • Diarrhea

  • Gas

  • Nausea

These symptoms are common and food may not always be to blame. Many factors can cause digestive distress, including:

How does food sensitivity testing work?

A food sensitivity test requires you to mail in a sample of blood or saliva, which measures antibody levels for a long list of foods — usually upwards of 100 different foods. 

Food sensitivity testing should not be confused with food allergy testing, which measures different types of antibodies. Food sensitivity tests measure IgG or immunoglobulin G, and food allergy tests measure immunoglobulin E (IgE).

Results are provided for each food tested. The foods are usually given a score or color-coded by the amount of IgG antibody that was detected. Foods with the highest levels of IgG are considered the foods you are sensitive to and should remove from your diet.

Some food sensitivity tests include basic information on completing an elimination diet once you receive your results.

Accuracy of At-home Food Sensitivity Test Kits 

Antibody testing sounds scientific, but it turns out IgG antibodies are not a reliable method for identifying food sensitivities. 

Researchers have concluded that IgG in the blood is a normal immune response that occurs with exposure to all kinds of food in healthy people. In fact, researchers believe high IgG scores may actually be a sign of food tolerance. While other types of antibodies may indicate an allergy or infection, the presence of IgG is not a cause for alarm. 

It’s no surprise that foods you eat often (i.e. more exposure) may have higher IgG scores and be flagged as a potential trigger on food sensitivity tests. 

Food sensitivity testing may lead you to unnecessarily eliminate foods, which can increase your risk for nutrient deficiencies, create feelings of deprivation, increase stress around food choices, and contribute to disordered eating. Food sensitivity tests are also limited in the number of foods they test for, so they could miss a potential sensitivity.

For these reasons, many healthcare professionals and organizations, including the American Academy of Allergy, Asthma, and Immunology, do not recommend the use of food sensitivity tests.

An elimination diet, where you identify and remove suspected trigger foods for a period of time and then reintroduce them, is the best way to determine whether you may have a food sensitivity. 

The bottom line? A food sensitivity test likely won’t produce reliable results, which doesn’t help you improve your health and is a waste of your time and money.

Alternatives to Food Sensitivity Tests

If you suspect something in your diet isn’t agreeing with you or is causing digestive distress, there are a few options to help you get answers.

Start by keeping a food journal. For several weeks, record everything you eat and drink in a day. Note the timing of your meals and portion sizes, if possible. If you experience symptoms like bloating or diarrhea, write down when they occur. 

Checking in with your doctor is a good idea to rule out other conditions that may be causing symptoms.


Individual nutrition counseling with a registered dietitian can help you review your food journal, detect patterns, and link symptoms to potential trigger foods. We can also provide guidance on how to safely complete an elimination diet, such as a low FODMAP diet, to determine whether your suspected triggers are truly causing your symptoms. Reach out to us to get started today.

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