Mediator Release / MRT Food Sensitivity Testing

MRT food sensitivity testingWhile many people are becoming more familiar with the concept of food sensitivity testing, most still haven’t yet heard of the mediator release / MRT food sensitivity test!  

Ironically, out of all the types of food sensitivity tests out there on the market, the MRT test would be my #1 recommendation for those who may be suffering from symptoms of inflammation triggered by food sensitivities.

Read on to learn why, and to determine if MRT food sensitivity testing could be a great next step for you on your journey.

What does “mediator” mean?

In this context, “mediators” are a class of chemicals in the body which are responsible for a variety of inflammatory symptoms often experienced in response to food sensitivities, most generally any of the following:

  • Redness 
  • Itching 
  • Swelling
  • Heat 
  • Pain 

There are many different types of mediators in the body, which are stored and conditionally released into the blood via different types of white blood cells in response to what they believe is a threat.

Examples and types of mediators 

Histamine is one of the most well-known mediators in the human body. 

  • Histamine is the chemical responsible for the inflammatory symptoms that show up in an allergic reaction (itching, redness, swelling, sneezing, constriction, etc.).

Other types of chemical “mediators” responsible for inflammation in a food sensitivity reaction include, but are certainly not limited to:

    • Cytokines
    • Prostaglandins
    • Thromboxanes
    • Leukotrienes
    • Serotonin
    • Bradykinin
    • …And many more!

What is “mediator release”?

Mediator release is a biochemical reaction responsible for the symptoms of both food allergies and food sensitivities (which are two totally separate types of adverse food reactions). White blood cells hold mediators intact (inside the cells) until they’re prompted by a type of protein, called an “immunoglobulin” which signals the white blood cells to release the chemical mediators out into the bloodstream. 

The process of mediator release occurs only when the immune system perceives a particular substance in the blood to be a threat to the body.  

  • In a healthy immune response, mediators are released only during times of illness (such as when our immune system is fighting off a virus or infection).  
  • However, among people with an unhealthy immune response (such as in food allergies, food sensitivities, and/or an autoimmune disorder), particles from certain foods and/or chemicals are mistakenly perceived by the immune system to be an enemy/invader. 

Mediator release in white blood cells - during Food SensitivitiesWhat are food sensitivities?

In food sensitivities, certain particles from food or chemicals get mistakenly flagged as invaders. In response, a variety of white blood cells from all different parts of the body will receive the signal and then release mediators into the blood.

The result is that eating certain foods or chemicals in food will lead to a cascade of unwanted symptoms whether it be a few hours or up to 3-4 days after a reactive food/chemical was consumed.

Symptoms of food sensitivities

The most common symptoms of food sensitivities found to be associated with inflammation caused by mediator release include, but are not limited to:

  • Leaky gut
  • Diarrhea
  • Stomach pain
  • Heartburn/reflux
  • Ulcers
  • Itching
  • Skin breakouts/ rashes
  • Joint pain
  • Muscle pain
  • Headaches/migraines
  • Autoimmune conditions
  • Hormonal imbalance
  • Fluid retention

How do food sensitivities cause inflammation?

Below is a detailed infographic which explains the step-by-step process of mediator release in a food sensitivity reaction.

How food sensitivities cause inflammation, and clinical indicatiors for mrt food sensitivity testing

MRT Test Frequently Asked Questions

Is MRT a type of allergy test?

Food sensitivities are NOT the same as food allergies, and mediator release testing does not test for allergies! (The gold standard for allergy testing is to get an IgE skin panel at an allergy clinic.)

While both food allergies and food sensitivities involve the immune system, their mechanisms and symptoms in the body are very different.  

  • Allergic reactions take place ONLY in mast cells (a specific type of white blood cell that lives on the mucous membranes of the body – so the gut, skin, lungs and throat).
  • Histamine is the ONLY type of mediator involved in allergic reactions, while food sensitivities can involve any type of mediator.
  • The type of antibody responsible for an allergic reaction (immunoglobulin E, aka “IgE”), is very specific, unlike food sensitivities which involve a broad scope of immunoglobulin pathways.

Food intolerances are another type of adverse food reaction which often get mistaken to be food allergies or sensitivities. 

What makes MRT testing different from other types of food sensitivity tests?

The MRT test is the only version of a food sensitivity test which assesses the full picture of what’s going on. 

It doesn’t just measure ONE pathway in your immune system – it measures the density and volume of your white blood cells before and after getting exposed to each individual food and chemical on the panel.

Who is a good candidate for the MRT food sensitivity test?

In recent years, migraines, joint pain, diarrhea-predominant irritable bowel syndrome (IBS-D), inflammatory bowel diseases (IBD), and certain types of autoimmune disorders are found to correlate with mediator release and food sensitivities.

If you’re experiencing any of the following, the MRT test could be very informative and enlightening for you:

  • Diarrhea-predominant IBS
  • Crohn’s disease
  • Ulcerative Colitis
  • Celiac disease
  • Gastritis
  • Peptic ulcers
  • Heartburn/reflux
  • Urticaria (hives)
  • Acne
  • Psoriasis
  • Eczema
  • Polycystic ovarian syndrome (PCOS)
  • Fibromyalgia
  • Arthritis
  • Hashimoto’s (autoimmune hypothyroid)
  • Grave’s disease (autoimmune hyperthyroid)
  • Lupus
  • Mast cell activation syndrome (MCAS)
  • PANDAS syndrome
  • Migraines
  • Headaches
  • Lymphedema
  • Chronic fatigue
  • Major depressive disorder (MDD)
  • Anxiety disorder
  • Autism spectrum disorder (ASD)
  • Schizophrenia
  • Epilepsy
  • And more!

Who is NOT a good candidate for MRT?

While food sensitivity reactions can lead to lots of different unwanted symptoms, it’s important to note that MRT testing is not for everyone!

I would not recommend getting the MRT test if there’s a tendency towards disordered eating or an unhealthy relationship with food.  

  • Food sensitivity testing (even with the best of intentions) comes with the potential to trigger behaviors of dietary restriction, anorexia, orthorexia, binging, and/or bulimia among people with eating disorders.

I also wouldn’t recommend pursuing MRT if you aren’t ready to commit to yourself and take the time to do things like food logging and meal planning/prepping.

  • (Throwing money at problems is not enough to make them go away – you’ve still gotta do the work!) 😉 

MRT testing is also not going to be as helpful or relevant for people experiencing conditions that are NOT directly linked with mediator release/food sensitivities, such as:

  • Constipation without diarrhea
  • Gas 
  • Bloating
  • Conditions caused by physical trauma/injury 
  • Acute illnesses/infections

Which foods and chemicals are tested?

How much does MRT testing cost?

  • The retail price for the full panel of 170 different foods and chemicals is $695. 
    • Some practitioners may charge more, and others may bundle this test into a full program for a reduced rate on the test itself.  
      • When you work with a certified LEAP therapist, you’ll usually also have the opportunity to receive custom meal planning services (which require LOTS of time and for us on the back-end but will be VERY helpful for you). This is a common reason why some practitioners charge more than the retail price listed, and it’s still well worth the investment!
  • Discounted rates are available for my clients who enroll in any of the following:

Is the mediator release test covered by insurance?

  • Unfortunately MRT testing is not covered by any insurance plan. 
    • However, you may use a FSA/HSA card to pay for this test and you can also use those types of cards to cover any blood draw fees associated with MRT.

Why is MRT more expensive than other food sensitivity tests?

  • MRT food sensitivity testing paired with lifestyle eating and performance (LEAP) therapy is the gold standard for addressing food sensitivities.  This approach will give you the full picture of what you need to know and implement so you’re unraveling and resolving imbalances holistically – at the cellular level. 
    • Other tests are only showing you a sliver or slice of the pie! They only measure individual pathways which are a fraction of the full picture of mediator release.

WIll I have to avoid the “reactive” foods and chemicals on my MRT panel forever?

  • Not necessarily!  We’ll re-introduce and re-test the foods that showed up to be moderately reactive after ~3 months, and then we’ll re-test the foods that show up to be highly reactive after ~6 months.  
    • Whether or not you can resume eating these foods will depend on how your body responds and how you’re feeling!

Will MRT and LEAP therapy provide me with everything I need to heal and recover 100%?

  • While these interventions are extremely powerful (and can often lead to people feeling up to 50-90% better in a matter of weeks), MRT and LEAP are not enough as a stand-alone intervention to serve as a “be-all end-all” cure to your chronic health condition.  
    • LEAP and MRT are meant to complement and enhance your journey, alongside other interventions whether they be medical or nutritional (or both).
  • Given that food sensitivities typically go hand-in-hand with dysbiosis and leaky gut, the MRT + LEAP approach is most effective when paired with GI mapping.

How to get the MRT food sensitivity test:

While simply running the MRT test and getting results to satisfy curiosity is all most people want, stopping there is not enough to help you from a “best practice” standpoint.  Navigating food sensitivities can get confusing and overwhelming, very quickly!

Work with a certified LEAP therapist

I highly recommend embarking on your MRT journey alongside a certified Lifestyle Eating and Performance (LEAP) therapist, so that you’re supported and equipped with the proper guidance and clinical nutrition supervision along the way.

  • A certified LEAP therapist (CLT) is a type of functional dietitian-nutritionist who has received specialty training in the immune system, adverse food reactions, and mediator release testing.  
    • Our mission is to help you to fully interpret and understand your test results, co-design a custom eating plan that helps you make quantum “leaps” on your journey (pun intended), and set you up for long-term success!
  • A CLT will use clinical discernment to help you determine whether MRT food sensitivity testing is appropriate for you or not.

The LEAP Immunocalm diet protocol

CLT’s are also trained to guide and coach clients through an optional 6-part LEAP “Immunocalm Diet” (also referred to as an “oligo-antigenic” plan), which is essentially a customized eating plan we’ll co-create together to incorporate all of your body’s BEST foods in a nutritionally sound way.  

  • The Immunocalm eating plan is something we design and craft together based on your food preferences, eating patterns, goals, and MRT test results.

When properly followed, in my clinic I’ve observed the Immunocalm approach can lead to 50-90% improvement (from a symptom reduction standpoint) within the first few weeks!

If you’re interested in working together on your journey, I’d love to support you!  Below is a step-by-step outline of how you can obtain the MRT test through working with me.

MRT and LEAP: step-by-step

  1. We’ll chat before or during our first consultation, to make sure MRT Is a good fit for you based on your unique clinical picture and nutrition/health goals.
  2. I’ll send you an online requisition form (via secure document sharing in my client portal), along with a PDF of instructions on next steps.
  3. You’ll receive a MRT test kit in the mail, delivered to your address on file with me.
  4. The next step is to book a blood draw with a local lab in network with Oxford Biomedical Technologies (the company through which you’ll receive the Mediator Release test kit and results booklet). See below for an infographic with further details.
    • Make sure to bring the requisition form and MRT test kit to your appointment!
  5. Once your blood draw is all set, and the samples have been submitted, the level of reactivity (degree of mediator release) occurring within your white blood cells from the sample collections will be measured against a control as well as 170 different foods and chemicals.
  6. Within a week of your blood draw, I’ll receive a secure PDF with your results. You’ll also receive a hard copy of your results within a 50+ page booklet for you to refer to so you can learn more about how to navigate food sensitivities and possible dietary restrictions through restaurant planning and recipe modification.
  7. Before making any dietary changes you’ll be prompted to complete a baseline symptom survey, which we can refer back to down the road to assess your progress!
  8. We’ll go over your results in our next 1:1 meeting and during that time we’ll also co-create your custom LEAP eating plan.  It can be in phases or we can modify this to accommodate your lifestyle and preferences.
  9. You’ll begin the LEAP eating plan we crafted together in our appointment.  You will be instructed and encouraged to keep a detailed food-symptom journal so we can get as much feedback as possible about what’s working and what isn’t!
  10. We’ll follow up weekly or as needed, depending on the amount of support you need along the way.

MRT Test - Blood Draw Specimen Collection and Shipping ProcessMRT testing – let’s work together!

To learn more about the different ways we can work together and how you can get started, I invite you to check out the options below to determine which direction feels like the best fit for you:

1:1 Services

The Complete Gut Repair Roadmap Group Program

The Complete Gut Repair Online Course

Let’s chat!

You can also search on to find another certified LEAP therapist near you.

Wishing you the best of luck, wherever your journey takes you!



  1. Abdulkhaleq, L A et al. “The crucial roles of inflammatory mediators in inflammation: A review.” Veterinary world vol. 11,5 (2018): 627-635. doi:10.14202/vetworld.2018.627-635