Do Food Sensitivity Tests Work? Answers, Options, and More

Medically Reviewed By Jerlyn Jones, MS MPA RDN LD CLT
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A food sensitivity test determines whether you have an adverse reaction to a specific food. It works by checking your immune response to different foods. Many people have touted the potential benefits of food sensitivity tests. However, the test is not a diagnosis nor a substitute for a clinical test or a professional treatment plan.

This article discusses food sensitivity tests, including their applications and reliability.

Food sensitivities 

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Food sensitivity is when you have an adverse reaction to a specific food. It is usually not life threatening, but it can cause bloating, headaches, and diarrhea.

The exact causes of food sensitivities are unknown. However, experts suspect that an increase in specific immunoglobulin G (IgG) antibodies may be involved. 

IgG antibodies are immune system proteins that can react strongly to certain foods. They are the most common type of antibody in your blood.

Food sensitivities can often mimic food intolerances and allergies. However, the three are not the same.

The table below lists the main differences:

Food sensitivity Food intolerance Food allergy 
DefinitionThis is when you have an unpleasant reaction to a specific food.This is when you have difficulty digesting certain foods.This is when your immune system mounts an aggressive defense against a specific food.
CauseThis develops from IgG reactivity.This is unrelated to antibodies or the immune system.This develops from immunoglobulin E (IgE) reactivity.
SymptomsSymptoms can include fatigue, stomach pain, and skin rash.Symptoms can overlap with those of food sensitivities.Symptoms can include hives, difficulty breathing, wheezing, and dizziness.
Onset of symptomsSymptoms may delay hours to days.Symptoms may delay hours to days.Symptoms can begin within minutes of exposure.
SeveritySymptoms are typically not life threatening.Symptoms are typically not life threatening.Symptoms can be life threatening.

Read about food intolerance vs. food allergies.

What food sensitivity tests do

One of the most common ways people identify food sensitivities and intolerances is through an elimination diet.

An elimination diet is when you deliberately cut out certain foods to find out what you may be sensitive to. It can be effective in helping you identify intolerances, but it has some disadvantages, including:

  • the need to remove potentially important nutrients from your diet
  • the possibility that identifying the specific foods you are sensitive to may take some time

A food sensitivity test attempts to provide a more efficient assessment than an elimination diet. It measures your immune response to different foods without requiring initial nutrient removals or extended waiting periods.

Test providers typically use the following steps to perform the test:

  • They collect a small amount of your blood, hair, or other bodily samples.
  • They measure the amount of IgG antibodies in your sample for different foods. 
  • They provide a list of the various foods you may be sensitive to based on your IgG reactivity levels for the different foods.

There is also an at-home testing option that allows you to begin the test at home. You mail in test kits with your blood or hair sample.

Is food sensitivity testing right for you?

Food sensitivity tests may provide some insights, but there is not enough evidence to support their efficacy.

They may flag safe unreactive foods as unsafe. They may also wrongly diagnose food sensitivities when, in fact, a more serious digestive condition is causing your symptoms.

The most effective way to identify potential food sensitivity is to monitor your symptoms and the foods you eat. 

It is also important to report any concerning symptoms to your doctor for diagnosis and treatment.

What type of food sensitivity test is best? 

The type of food sensitivity testing to choose will depend on your needs.

The table below lists the pros and cons of the two options:

Lab food sensitivity testAt-home food sensitivity test
Procedure A test provider will collect your samples and take them to a lab for testing.You will buy test kits and begin the test at home.
AccuracyLab testing may be more accurate and reliableAt-home testing may be less reliable.
CostThe cost of lab testing may be higher.The cost of at-home testing may be lower.

Reliability of food sensitivity tests

A study from 2018 shows that many tests for food sensitivity and adverse reactions to food are unproven or disproven techniques.

Another study from 2020 noted that there is “no criterion standard test” to identify food sensitivities definitively.

Even if a food sensitivity test accurately identifies several reactive foods, it’s typically unlikely to identify all reactive foods. The most effective way of discovering food sensitivities is to monitor your symptoms and what you eat. Discuss any reactions you experience with your doctor.

When to see a doctor

Speak with your doctor if you have severe or persistent food-related symptoms. Standard diagnostic tests may help determine the exact cause.

Allergy and intolerance testing 

Food allergy and food intolerance tests differ slightly from food sensitivity testing.

Food allergy testing checks if your food-related symptoms are due to an allergic reaction. There are many types, including:

  • Oral challenge test: A healthcare professional will have you consume a small amount of the suspected food. They will then monitor you for any changes.
  • Skin prick test: A healthcare professional will place a small amount of the suspected food on your skin. They will then prick your skin to see whether you have any reaction.
  • A blood test: A healthcare professional will take a small blood sample. Next, they will measure your IgE antibody levels.

Intolerance testing checks to see if your food-related symptoms are due to digestive problems. It typically uses breath tests or the elimination diet method.

Frequently asked questions

Here are other questions about food sensitivity tests. They have been reviewed by Jerlyn Jones, M.S., M.P.A., R.D.N., L.D., C.L.T.

What are the 3 most common food intolerances?

Lactose, gluten, and FODMAP intolerances are three of the most common food intolerances. FODMAP is an acronym for a range of compounds, fermentable oligosaccharides, disaccharides and monosaccharides, and polyols.

What are the signs of food sensitivity?

Symptoms of food sensitivity can include stomach pain, diarrhea, and bloating. Other symptoms include headaches and gas.

Summary

A food sensitivity test helps to determine whether you have adverse reactions to specific foods. Food sensitivity is when you have an unpleasant reaction to a specific food. It can cause stomach pain, bloating, and diarrhea.

Food sensitivity tests can provide some insights, but they are not a diagnosis. Report severe or persistent food-related symptoms to your doctor for diagnosis and treatment.

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Medical Reviewer: Jerlyn Jones, MS MPA RDN LD CLT
Last Review Date: 2022 Nov 29
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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