ALCAT and MRT: You either love ’em or you hate ’em. In this post I will explain why I’m generally in the later camp.

ALCAT and MRT work via the same principle: Put an immune cell (Leukocyte/white blood cell) on a dish, expose it to antigens (foods), and watch to see if the cell swells or shrivels up. These two tests use different methods to observe this reaction, but they are similar enough that I will cover both.

The big “selling point” for these tests

There are many blogs, YouTube videos, and clinicians on the internet singing the praises of these two tests, and it all boils down to one main selling point. Proponents of these tests point out that there are multiple pathways (triggering mechanisms) for food to activate an immune response (IgG, IgM, amines) but their presence does not necessarily mean that an immune reaction will happen. Instead of measuring the triggering chemicals (for example, IgG), these tests aim to assess the end result: immune responsiveness to a food.

The single biggest problem with ALCAT and MRT testing, simply put:

When in your life will you ever expose your immune system to an antigen this way (aside from vaccines)? Food particles normally go through many, many processes and steps before they come into contact with your immune system. How can we expect tests that bypasses the entire normal digestive process and antigen presentation process to reliably test for immune reactivity against food? In short, we cannot.

This is seen in the picture I drew below, but I’ll summarize it in text, too. Normally food antigens have to pass through the following steps before provoking an immune response. Please note, allergies, histamine reactions, and food intolerances are different and provoke a different kind of reaction (more here).

Steps between food and your immune system:

  1. Chewing and salivary enzymes

  2. Stomach acid (very acidic)

  3. Digestive enzymes and bicarbonate (basic)

  4. More enzymes

  5. Brush border enzymes

  6. Bacteria, yeast, parasites, viruses in the gut

  7. Microbial metabolites and toxins

  8. Changes in pH from microbial metabolites

  9. Interaction between nutrients in the food and antigens? Or between multiple antigens? Fiber and antigens?

  10. Mucous and antibodies

  11. Absorption by gut epithelial cells

  12. “Sampling” of antigens by dendritic cells (DCs)

  13. “Antigen presentation” by DCs to other cells (T or B cells)

  14. WBC movement into the blood and lymph

  15. Interaction of multiple immune cells (ex: production of antibodies by plasma cells, binding of antibodies to mast cells, histamine binding to mast cells and TH2 cells…)

Another problem with MRT and ALCAT Testing:

Both tests evaluate changes on leukocytes “including monocytes, lymphocytes, eosinophils, basophils, and neutrophils.” Holy macaroni, is that broad! These five types of cells differ widely in their behavior and skills. Even within each category, there are many different types of cells (ex: lymphocytes = T cells, B cells, NK cells) that do very different things.

How can you predict what is “normal” and “abnormal” for a test when you’re comparing apples to zucchini? In my opinion, you cannot. For example if you test the gluten antigen against 10 different samples, but you’re using a different type of white blood cell every time, how can you possibly standardize the results? Can we really expect the same reaction from all of the troops in such a diverse army?

Unfortunately, there isn’t a perfect test for food sensitivities. I think Cyrex is the closest, for those who want a test to guide them, but that’s all it is- a guide. The ultimate challenge is to eliminate a food for a few months and reintroduce it.

Wishing you a diverse and healthy diet,

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