In part 1 of this series, we looked at what food sensitivities actually are, and how they’re different from food allergies and food intolerances. In part 2, we looked at what symptoms can indicate whether food sensitivities are present, how our bodies can have an adverse reaction to something as innocuous as food, and how food sensitivities develop over time.
I recommend you take a few minutes to read both.
This week, I want to talk about how to determine specifically what foods, if any, are causing adverse reactions in your body. In part 2, I gave you a list of symptoms and health concerns that have been linked to food sensitivities. Having one or more of these symptoms doesn’t mean you necessarily have food sensitivities, but it warrants further investigation. It’s critical that you find out exactly what foods you’re sensitive to so that you can temporarily eliminate them from your diet and begin the healing process.
Unfortunately, testing for food sensitivities isn’t clear cut which is why there is some controversy in the health community around it. There are many different testing options, and not all are created equal. There are several complicating factors:
There are many different mechanisms for driving an adverse response to food: some immune-mediated, some cell-mediated. Most testing processes look at one or two specific mechanisms, which means they necessarily aren’t getting the whole picture.
The question of whether you are sensitive to a particular food doesn’t have a yes/no answer. You can be mildly sensitive to one food, and more severely sensitive to another food. These reactions occur on a spectrum - different shades of gray.
It can take up to 3 days for an adverse reaction to manifest in your body. That’s a long time! And presumably, you’ll have eaten many other foods in the interim. This makes it very challenging to track without formal testing. Some basic approaches like food journaling can be insightful, but very difficult to identify exact patterns because there are so many possibilities. Is it dairy or is the Sorbic acid used to make the cheese? Is it pork or is it potassium nitrate? Maybe potassium nitrite? How about FD&C red dye #5 or #40? See what I’m getting at? This is crazy making, indeed!
And lastly, food sensitivities compound on each other. You may have mild reactions to several foods that you eat in the same meal, and thus provoke a more serious reaction than you would if you were to eat these foods in isolation or without other triggering foods. Since we don’t typically eat just one food at a time, this is a major complicating factor. There are many examples of this including histamines and tyramine. Ack!
Let’s look at the different ways of testing for food sensitivities:
1) Elimination diet
An elimination diet is much like what it sounds: you temporarily eliminate potentially offending foods for a period of time to clear them from your system (usually 10-14 days minimum Three weeks is actually better). Afterwards, slowly reintroduce these foods on a specific schedule (usually one food introduced every 3 days to account for delayed reactions) watching carefully for adverse reactions and tracking them using a food journal
This method can be a great starting point, but it’s not conclusive. The key challenge is in the definition of “potentially offending foods.” Most elimination diets, including RESTART® and GOOD DECISIONS® eliminate the most common culprits: gluten, dairy, corn, grains, soy, and/or eggs. But what if you’re sensitive to avocado? Or lettuce? Or tomatoes? Or any other food or chemical for that matter? As you can see, it becomes impractical in a hurry to eliminate everything from your diet. To slowly introduce all foods, one every three days, would require a discipline that is difficult to fathom. Furthermore, it doesn’t solve the problems of combined foods and degrees of sensitivity.
2) Coca's pulse test
This is another DIY test and I do like this test because it can help you tune into your body for an overt physiological response: a speeding pulse. BUT, not all sensitivities drive up the pulse and it doesn’t address the fact that sometimes you can eat combinations of foods that are mild sensitivities. This is another good starting point, but not conclusive.
3) Mechanism-specific tests
As I described earlier, there are many different mechanisms in your body for initiating an adverse reaction to a specific food. Some are immune-mediated, some are cell-mediated. A mechanism-specific test is looking for a specific mechanism to be triggered by the ingestion of a food: usually we’re talking about IgA, IgG, IgE, or IgM type responses.
Now, the ELISA and RAST tests can be quite accurate for testing one or two specific mechanisms, but what about the mechanisms they are NOT testing for (of which there are many). Conversely, this is one of the reasons why food allergies – or Type 1 hypersensitivities as I explained in Part 1 – are so easy to identify: we’re only looking for one mechanism, the release of IgE. Unfortunately, when it comes to the more complex category of food sensitivities, these tests don’t give us the full picture.
testing for (of which there are many)
4) Mediator-measuring tests
The last type of test takes the middle man out of the picture. Instead of measuring the mechanism for initiating an adverse reaction to a food, it goes straight to the end result: the release of mediators such as histamines, cytokines and prostaglandins. They are responsible for actually causing inflammation in the body. While there are multiple different pathways (or mechanisms) for triggering the release of these mediators, what’s actually important when it comes to determining whether a food causes an adverse reaction or not is whether these mediators are released on exposure to that food. Mediator-measuring tests look for this response, and thus eliminate one of the critical complicating factors of food sensitivity testing overall. My preferred test by far – and in my opinion the gold standard in the world of food sensitivity testing – is the MRT170 (Mediator Release Test) by Oxford Biomedical Labs.
Here’s why I love it:
The MRT170 tests a wide variety and long list of foods – not just the most common sensitivities. It tests 150 different foods and chemicals – it’s not every food you could possibly eat, but it’s a darned good representation.
The MRT recognizes that there are certain chemicals found in some foods either naturally or added through food processing that can trigger adverse reactions. They test for these in addition to the foods, which can provide very helpful information about whole categories of food. A good example of this is solanine, the chemical in nightshades (potatoes, eggplant, peppers, tomatoes) that some people are sensitive to. You’ll hear broad recommendations of “oh, don’t eat nightshades – they’re really inflammatory” but that’s not the case for everyone. Testing for a solanine sensitivity will be helpful to know whether nightshades are truly an issue for you or not.
The MRT accounts for shades of gray and shows the degree of sensitivity for each food. This is extremely helpful when coming up with a diet protocol to address these sensitivities.
It is over 90% accurate, which is almost unheard of in the world of food sensitivity testing.
It is based on physiological principles that are broadly supported in the scientific literature and by published studies.
And, perhaps most importantly, in my practice I have seen the best results when working with the results of this particular test.
That said, the MRT170 isn’t perfect. It’s not 100% accurate, which doesn’t exist in 2021 to my knowledge. Additionally, it doesn’t identify IgE food allergies (type 1 hypersensitivities), because that response doesn’t occur in the blood. But most people know the true food allergies they have – what’s more complex and difficult to pinpoint are the food sensitivities, the type 3 and 4 hypersensitivities that don’t involve an IgE immune reaction.
Note about skin testing:
Another test used to identify adverse reactions to food is skin testing – this often known as the “scratch test” and is the test most commonly used by medical professionals.
In this type of test, the skin is irritated with the specific antigen (beef, egg, and so on). If there is an allergy, then the immune cells will release histamine, which will appear as a red inflamed area on the skin, much like a mosquito bite.
I haven’t included skin testing in my list of options above because it’s only useful for identifying true food allergies – those type 1 hypersensitivities we described in Part 1 – and is utterly useless for food sensitivities. Many people go to their doctor, have this test done, and believe that it is conclusive for all adverse reactions to food, so I want to clear up that confusion.
Note: while it’s the most commonly used test and the gold standard for airborne allergies (pollens, dander, and so on), this test isn’t all that accurate for food allergies either.
So, now that you know what foods you’re sensitive to, you can just eliminate them for a while and all is good, right? Not so fast… I wish it were that simple but that’s one of the challenges of working with food sensitivities. It’s a lot more complex than just eliminating the trigger foods.
The trouble with relying exclusively on food sensitivities
My training as a functional nutritional therapy practitioner has taught me how that gut healing must take place to prevent food sensitivities from developing in the first place (see part 2 for more information on this process).
If we simply remove the trigger foods from the diet, we’re alleviating the damage in the short term, but we’re not actually getting to the root of the problem, which lies in the digestive process: why is improperly digested food getting into the blood in the first place?
When paired with gut healing, removing food sensitivities can be a powerful and integral part of the healing process. Alone, both of these strategies – gut healing and removing food sensitivities – are moderately effective. Together, they are far more than the sum of their parts. The results were tremendous and life-changing.
The two-pronged approach to healing food sensitivities
Using this two-pronged approach – deep gut healing with the temporary elimination of food sensitivities from the diet – I was also able to resolve mysterious and chronic issues. Now, I have incorporated this approach into my practice and am continuing to see incredible results.
Working with food sensitivities is an important part of the puzzle, but not the whole picture. You really have to address the root cause of the “leaky gut” which is gut dysbiosis. If you don’t do both, more often than not, new sensitivities will develop and all that happens is a diminished list of foods the body can handle. At the same time, gut healing alone without identifying and removing food sensitivities is often ineffective because those foods are causing inflammation.
Here’s an analogy:
Imagine you have a big scrape along your arm and you use aloe, band-aids, neosporin, etc to promote healing. But every day you walk alongside a brick wall and scrape your arm against it. At best, this scraping would slow your healing; at worst, it would exacerbate the problem and make the wound even more irritated and inflamed.
Food sensitivities are like the brick wall: exceedingly irritating to the gut lining you’re trying to heal. Unless you remove them while you do the healing work, you are at best slowing down your progress, and at worse exacerbating the problem the whole time.
In some cases, the very healing foods you’re eating can be sensitivities! I was sensitive to histamines which is found in sauerkraut. The large quantities of homemade sauerkraut I was eating was actually working against me, even though for most people it’s an important part of the healing process because it is a fermented food and contains wonderful strains of good bacteria.
The 4-step process for healing food sensitivities
Here is my 4-step process for healing food sensitivities and simultaneously laying the foundation for some true healing in many other areas of your body:
Identify food sensitivities.
Determine the health and function of your digestive system. How well is it working? Are there factors such as parasites, fungal overgrowth, or imbalances in your microbiota that are blocking your body’s ability to heal? The GIMAP test can provide this information.
Heal the gut AND eliminate food triggers simultaneously. You’ll need to do this work with a qualified practitioner. Generic protocols aren’t good enough - you need specialized, personalized and targeted healing protocol based on your test results.
Reintroduce foods 3 - 6 months after your symptoms have gone away, progressing very slowly to ensure each food is no longer a trigger for you.
This process is technical and should be done under the guidance of a qualified health practitioner.
I wish I could say it’s a DIY protocol – but the testing involved, the interpretation of those tests, and the development of a healing protocol both from a dietary and supplement perspective are too technical unless you’ve been specifically trained.
The good news is, I have received the training and have used the protocol with patients and clients with excellent success.
I hope this series has helped to demystify and clear up some of the confusion around working with food sensitivities. If you have more questions I haven’t answered, please post them in the comments below and I’ll be sure to answer them, either here or in a future post!