Can I Test for a FODMAP Intolerance? The Truth About Food Sensitivity Tests

by | Aug 16, 2023 | IBS, Low FODMAP

In a time marked by a growing emphasis on holistic wellness and personalized healthcare, it’s no surprise that health trends have emerged to satisfy these desires. Among these trends, food sensitivity testing has gained significant popularity, promising to uncover hidden sensitivities that could be contributing to various health issues. One such issue is FODMAP intolerance.


But are food sensitivity tests worth it, and can they actually identify FODMAP intolerance? In this blog post, we will review the differences between allergies, intolerances, and sensitivities and address the limitations and potential harms that can come from relying on these tests for dietary guidance.


And for further information on how to tell fact from fiction, head to my blog The Truth about Nutrition: How to Tell Fact from Fiction.


Food Intolerances vs. Food Allergies vs. Food Sensitivities – What’s the Difference?

While these terms are often used interchangeably, they’re actually different conditions. Here’s a run-down of what food intolerances, food allergies, and food sensitivities are.


Food Intolerances

When a person has a food intolerance, it typically refers to their body’s inability to process or digest a certain food or group of foods. They are often dose-responsive, meaning a certain amount of the food has to be eaten before symptoms arise.


One of the most common food intolerances is lactose intolerance. If a person has lactose intolerance, their body lacks the enzyme (known as lactase) needed to break lactose down. This can lead to unpleasant digestive symptoms like bloating, gas, and diarrhea.

Another common food intolerance is FODMAP intolerance. FODMAPs are a type of carbohydrate that are not digested in humans. Because they’re not digested, they enter the colon and get fermented by the gut bacteria. This can lead to unpleasant symptoms like gas, bloating, diarrhea, and constipation. It’s thought that people with irritable bowel syndrome (IBS) have a FODMAP intolerance.


Food Allergies

Food allergies are a more serious reaction and involve the immune system. Allergies are IgE-mediated. IgE is a type of antibody that your immune system makes when it’s exposed to an allergen. About one to two percent of adults and fewer than ten percent of children have food allergies.


When a person eats something they’re allergic to, their immune system produces an overblown response to the food. One of the best examples of a food allergy is a peanut or seafood allergy. Exposure to peanuts or seafood can be potentially life-threatening for people with allergies to these foods because it can lead to low blood pressure and difficulty breathing.


If you think you have a food allergy, you should consider allergy testing, especially if you have severe symptoms. If you are allergic to something, you must avoid that food completely and carry an Epi-Pen with you for treatment if you are accidentally exposed.


Food Sensitivities

Many people experience symptoms after eating food that are not related to food intolerances or food allergies. Some of the common symptoms of a food sensitivity include joint pain, stomach pain, fatigue, rashes, and brain fog. While there are still a lot of unknowns when it comes to food sensitivities, it appears that when certain people eat certain foods, their immune system is triggered.


One of the most common triggers of food sensitivities is gluten. Non-celiac gluten sensitivity (NCGS) affects between three and six percent of the general population. However, unlike celiac disease (which can be diagnosed through a blood test and intestinal biopsy), there is no reliable test for NCGS.



Understanding Food Sensitivity Tests

Food sensitivity tests are often ordered by naturopaths or other alternative healthcare providers. Here are some of the most popular food sensitivity tests:


IgG Testing

IgG (another type of antibody) testing is one of the most popular food sensitivity tests. Some popular IgG food sensitivity tests include Life Labs Food Sensitivity Testing and Dynacare Food and Digestive Health. However, these tests are unreliable because IgG production is a normal immune response to several commonly consumed foods. 


In other words? If you eat those foods often, you’ll get a positive result for them on your IgG test. It’s not telling you what you’re sensitive or intolerant to – it’s simply telling you what you’ve recently eaten.


Because of a lack of scientific evidence to support its use, the American Academy of Allergy, Asthma & Immunology and the Canadian Society of Allergy and Clinical Immunology have both recommended against using IgG testing to diagnose food sensitivities.


KBMO Fit Test

The KBMO Fit Test is a delayed food sensitivity test that tests 176 foods, food colourings, food additives, and microbes used in food production. According to the company, the tests measures IgG, Immune Complexes, and the most common food-related pathways in the body.


Measuring these parameters supposedly enables the test to identify food sensitivities, inflammation, and “leaky gut” from a single test. However, this test has not been studied in rigorous trials, and no scientific evidence supports its use.


MRT Test

The MRT test, also known as the Mediator Release Test or the LEAP test, is a food sensitivity test that measures the inflammatory response to food and food chemicals. It is said to be more accurate than traditional IgG or Immune Complex tests because it measures the actual inflammatory response in the body.


While it was previously used by dietitians, the Commission on Dietetic Registration discontinued support for its use in 2016, citing insufficient evidence for its ability to diagnose food sensitivities.


Hair Strand Test for Food Intolerance

The hair strand test for food intolerance measures the mineral content of a person’s hair. It’s thought that if a “harmful” food is eaten, it will show up in the mineral makeup of the hair. However, it has not been scientifically validated. Plus, hair grows slowly, so it’s not a good indicator of what is currently happening in the body.


Regardless of which type of food sensitivity test you’re looking at, there simply isn’t enough scientific evidence to support their use in diagnosing food sensitivities. Plus, none of these tests are designed to identify FODMAP intolerance specifically.


Potential Harms of Food Sensitivity Tests

Still not convinced that you don’t need to do a food sensitivity test? Let’s review some of the downsides and potential harms of using these tests to diagnose food sensitivities:

  1. You end up with a short list of “safe” foods and a long list of foods you’re told to avoid. Avoiding many commonly eaten foods could lead to malnutrition and nutrient deficiencies.
  2. These tests can create a lot of anxiety about what you “should” and “shouldn’t” eat. In extreme cases, this could lead to disordered eating behaviours.
  3. They’re expensive. If you’re experiencing bothersome symptoms and taking time off work, expensive tests can put a huge dent in your savings.
  4. They can mask something that might actually be wrong (for example, an undiagnosed true allergy or Celiac disease).


Alternatives and Evidence-Based Approaches

When you have unexplained symptoms, it’s important to seek medical care to rule out any serious causes of your symptoms. If you suspect you have a food allergy, you need to consult with an allergist who can run evidence-based tests to determine what you’re allergic to.


If you’re struggling with digestive symptoms and have ruled out causes such as inflammatory bowel disease, Celiac disease, and colorectal cancer, you may have IBS. People with IBS have extra-sensitive guts and may be sensitive to foods high in FODMAPs.


If you suspect you may have a FODMAP intolerance, an elimination diet such as the low FODMAP diet can be instrumental in helping you determine which foods you don’t tolerate. However, this diet is very restrictive and should be done with the guidance of a dietitian who has experience with the low FODMAP diet.


Final Thoughts

Overall, medical experts and researchers agree that food sensitivity tests aren’t accurate or worth your money at this point in time. If you’re struggling with bothersome symptoms that you suspect may be related to an allergy, consider meeting with an allergy doctor to complete IgE allergy testing.


If you’re struggling with gut symptoms and suspect you have a FODMAP intolerance, working with a registered dietitian who can guide you through the low FODMAP diet can be helpful in determining which specific foods you’re sensitive to. Keren is Monash FODMAP trained and has completed and passed the Monash University Online FODMAP Course.


Click here to book a free 15-minute call with Keren to discuss your concerns and determine if you’re a good fit for working together.

Get in touch with Keren and book a free 15-minute discovery call today!

< !-- Global site tag (gtag.js) - Google Analytics -->