At-Home Food Sensitivity Tests Aren't Worth the Money, Experts Say


Fact checked by Nick Blackmer

Key Takeaways

  • At-home food sensitivity tests claim to help people find out if they have food sensitivities through a simple blood test.

  • Food sensitivity or intolerance is not the same as a food allergy.

  • Experts, including the American Association of Allergy, Asthma, and Immunology, do not approve of at-home food sensitivity tests because research does not support their use.

  • If you think that the symptoms you’re having are related to a particular food, it’s best to talk to your provider.

Food sensitivity tests claim to give you a personalized analysis of whether your body is sensitive to certain foods. The idea is that doing the test could help you figure out possible trigger foods for gastrointestinal symptoms, headaches, and tiredness.

Doing a food sensitivity test at home might be convenient, but they’re not cheap—most of them cost hundreds of dollars that you’d have to pay out of pocket because insurance won’t cover them.

Experts also have concerns about the accuracy of at-home food sensitivity tests, so are they even worth the cost? Here’s what experts say about food sensitivities and whether you should bother testing for them at home.

Related: What Is a Food Sensitivity?

How Do At-Home Food Sensitivity Tests Work?

At-home food sensitivity tests use a small blood sample that you can collect yourself by pricking your finger. You send your sample to a laboratory where it is exposed to different food proteins and analyzed for levels of a protein called immunoglobulin G (IgG). For a lot of these tests, an elevated IgG is reported as a food that has “higher reactivity.”

The immune system makes immunoglobulins to fight substances such as bacteria, viruses, and other harmful pathogens. There are different types of immunoglobulins, including IgG, IgM, IgA, IgD, and IgE. Of these, IgG is the most prevalent, making up around 70–75% of antibodies in the human body.

Wade Manaker, MD, a physician and an assistant professor at the Medical University of South Carolina, told Verywell that having elevated levels of IgG is not specific to your body’s response to food and could be a sign of many things, including “an overactive immune system, a bacterial or viral infection, a presence of inflammatory diseases, or an autoimmune disorder.”

Wade said that having high IgG levels after consuming a specific food is not necessarily a sign that the food is causing your symptoms or that you have a “sensitivity” to it. In fact, higher levels of IgG may even be a normal immune response to food.

Related: Why Do Food Allergies Happen?

Food Sensitivity vs. Food Allergy

Being told that you are sensitive to a specific food is not the same thing as being allergic to it. There is a big difference between food allergies and food sensitivities. Even though both can cause symptoms, they involve different biological processes and differ in how severe they can be.

A food allergy is rooted in your immune system and can be life-threatening. When someone with an allergy eats a food that they’re allergic to, their immune system mistakes it for a threat and releases immunoglobulin E (IgE) antibodies—not the IgG antibodies that some at-home food sensitivity tests look for.

Can You Buy an IgE At-Home Test?

There are some at-home food allergy tests that look for IgE antibodies in your blood sample. If you see an at-home test for food sensitivities or intolerances, it’s probably checking IgG. There are also some combination at-home tests that check for both IgE and IgG antibodies. Manaker suggests evaluating whether you have an allergy with your healthcare provider instead of relying on at-home IgE tests. And if you do decide to use an at-home IgE antibody test, you should review your results with your healthcare provider.

The immune response from a food allergy can cause symptoms like itching and mouth swelling, which usually come on soon after a person is exposed. People with severe food allergies can develop a reaction called anaphylaxis which can be deadly.

Food sensitivity is less severe and does not involve the immune system the way that a food allergy does. Instead of producing IgE antibodies, the body may make IgG antibodies in response to certain foods.

The symptoms of food sensitivity are usually just felt in the GI system—think bloating, gas, and diarrhea. These symptoms are also delayed, usually coming on several hours or even days after someone eats a food that they’re sensitive to. Some people have other symptoms like headaches and fatigue. While these symptoms are not pleasant, they’re not the kind of life-threatening symptoms that a true food allergy can cause.

There are also differences between food sensitivities and intolerances. Being intolerant to a certain food means that your body has trouble digesting it. For example, if you’re lactose intolerant, your body doesn’t have enough of the enzyme needed to break down lactose in dairy products, so you get symptoms when you drink milk.

Related: What Are the Most Common Food Allergens?

Are IgG Food Sensitivity Tests Worth It?

Some people feel like finding out which foods they are supposedly sensitive to and avoiding these foods has helped them deal with symptoms, but medical literature and experts are not sold on at-home tests.

In fact, the American Academy of Allergy, Asthma, and Immunology (AAAI) recommends against using IgG testing to diagnose food sensitivities. The Canadian Society of Allergy and Clinical Immunology has made a similar recommendation about at-home tests for food sensitivities.

The AAAI states that IgG testing “has never been scientifically proven to be able to accomplish what it reports to do.” While some data appears to paint the tests in a positive light, the AAAI clarified that “the scientific studies that are provided to support the use of this test are often out of date, in non-reputable journals, and many have not even used the IgG test in question.”

Related: How to Tell If You Have a Food Intolerance

While there are plenty of IgG tests available online, medical experts are not on board with proactively recommending that people buy them.

Purvi Parikh, MD, an allergist and immunologist with Allergy and Asthma Associates in New York and a spokesperson for the Allergy and Asthma Network, said people should not “waste their money” on the tests, adding that they are “usually aren’t covered by insurance as they are not validated and not evidence-based and often inaccurate.”

The AAAI also clarified that the presence of IgG is likely a normal response of the immune system to exposure to food—and higher levels of IgG in the presence of certain foods might be associated with tolerance to those foods rather than intolerance.

Related: Can You Be Sensitive to Food Additives?

Your Symptoms Might Not Be Food’s Fault

If you take an IgG food sensitivity test, you should review your results with your healthcare provider and follow their guidance.

“It’s worth talking with your healthcare provider to help you uncover whether or not symptoms may be food-related.” Sarah Anzlovar, MS, RDN, LDN, a Boston-based registered dietitian and owner of Sarah Gold Nutrition, told Verywell. “Sometimes, symptoms are less related to a specific food and more related to eating patterns like eating too fast, eating while stressed, or unpredictable eating schedules such as skipping meals.”

If you don’t have symptoms but do test “sensitive” for a food, Anzlovar said that there is no reason to avoid it, given the lack of accuracy surrounding home tests.

“Many companies test for upwards of 100 foods, spices, and herbs, which can leave you feeling like there are a lot of foods you can’t eat if they come back listed as a sensitivity,” Anzlovar said. “This can lead to a lot of unnecessary stress around eating and even disordered eating patterns. And stress and food restriction may actually exacerbate any symptoms you have—especially those that are related to digestion.”

What This Means For You

If you’re worried that you’re having symptoms related to a specific food, talk to your provider. Experts say that at-home IgG tests are not a reliable way to diagnose a food allergy or even a sensitivity/intolerance—which is not the same as a true allergy.

Read Next: Can You Be Allergic to Sugar?

Read the original article on Verywell Health.