From The Desk of Josh Gitalis

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food allergy

Go to a restaurant with a group of friends, and you can be rest assured that at least one person will have a  sensitivity to a certain food. You might even get prompted by the server to inform them of any foods your group needs to avoid. This scenario is becoming more and more commonplace.

Over the past 20 years, there has been a huge increase in allergies. People are becoming more and more sensitive to the foods that they are eating. Why is this happening? It is likely due to a number of factors that produce the “perfect storm”. Some of the factors included (but not limited to) are chemicals in our food, leaky gut syndrome, dysfunctional immune system, imbalanced microbiome, and nutrient deficiencies.

Allergy increase
Increase in allergies from 1990-2001. (Source: BMJ 2003;327:1142)

With people having so many different reactions to the food they eat, it can be quite confusing pinning down the culprit. And for good reason. Food reactions cannot be attributed to just one type of mechanism. There can be multiple mechanisms occurring at the same time or in isolation. My job as a practitioner, is to help my client determine the root of their food sensitivities through symptom analysis, detailed histories, and testing. Our goal is to find the cause.

It’s important to understand the different types of food allergies and sensitivities, so that we can navigate the landscape effectively.

Immune-Mediated Allergy

When I’m explaining the immune system to my clients, I use the example of law enforcement agents. In a country there are the highway patrol, border police, parking enforcement, SWAT team, and neighbourhood patrol. They all work for the same organization of law enforcement, but they react to different threats. The immune system is the same way. There are different players that react to different threats. Some of the them are called immunoglobulins, and they are allotted a letter to differentiate between them. For example, we have immuglobulin E (IgE), and immunoglobulin G (IgG), even immunoglobulin A (IgA) and immunoglobulin M (IgM). Each is responsible for a different response.

IgE Mediated Reactions

When we use the term “allergy” this is the reaction most people are technically referring to. IgE allergies are responsible for  immediate responses; such as anaphylaxis after a bee sting or eating peanut butter. IgE allergies don’t always have to be so severe, however. Symptoms such as headaches, hives, shortness of breath, and digestive upset are common. Reaction can also be brief or last for hours.

IgG Mediated Reactions

This is the type of reaction that is often mixed up with IgE reactions. Someone might say “I have an allergy to eggs”, when in fact, when IgG is involved, it is called a “food sensitivity”.

There are multiple labs now offering food sensitivity testing. They are easily accessible and easy to do. For some of them, all you need is a small amount of blood, which can easily be obtained by a skin prick.

In conventional immunology, they don’t recognize the validity of these tests. One of the reasons is that the tests are not standardized. Unlike IgE testing, each lab has their own methodology in determining food sensitivities. As a result, the IgG food sensitivity test is often discounted by immunologists as a valid diagnostic test. What is being missed with this all-or-nothing mentality, is that IgG testing can still be a useful tool in figuring out the cause of the patients symptoms.

What I’ve seen in clinical practice is that for some people this test provides information that leads to great results. For example, one client was getting eczema on her arms and eye lids. She did the test, found out she was sensitive to pineapple and eggs, eliminated those foods, and had complete remission of symptoms. I’ve had other clients that have done the test, and haven’t had such dramatic results, or have had no improvement at all. The reason this happens is because sometimes it’s a different part of the immune system responsible for the reaction (remember the law enforcement agents). Or, it’s not an immune mediated reaction at all.

Non-Immune-Mediated Reaction

Toxic Reactions

A few years ago a friend of mine told me about a “culinary adventure” he experienced. It all began one morning before heading to work, when he was in a rush. He had made himself a breakfast sandwich, and in his busyness, had forgotten to eat it. He decided that the best approach, would be to reheat it and take it to work. He quickly threw it on a styrofoam plate. Popped it in the microwave oven. Nuked it. And then proceeded to eat it in the car.

When he had finished consuming his breakfast sandwich, he noticed that part of the plate had melted into his sandwich, and he had subsequently consumed the plate without knowing. Shortly after he noticed this, he felt ill. He had to go back home and spend the day sick in bed.

This is an example of a toxic reaction. It is my guess, that anyone consuming styrofoam would eventually become sick. It’s just a matter of having enough of it. In my friends case, it seems like he got a good dose.

Toxic reactions can happen from any chemicals that might be in our food. The herbicide glyphosate, is quickly becoming known as one of the most toxic agrochemicals being used on our food. Some people are a lot more sensitive to this chemical, and can experience a variety of nasty symptoms as a result. This is but one example of a toxic chemical in our food, but there are many other pesticides, herbicides, fungicides, and larvicides, that can end up in our food.

Non-Toxic Reactions

One of the most well-known non-toxic reactions to food is an enzymatic deficiency known as lactose intolerance. In fact, seventy percent of the world is unable to produce the enzyme lactase after they are weaned from breast milk. Makes you wonder why they put dairy as a whole food group on many countries food guides.

When these individuals consume lactose (milk sugar), they are unable to break it down into smaller units (glucose and galactose). As a result, two things take place. First, the lactose creates an osmotic gradient that pulls fluids into the small intestine, resulting in diarrhea. Second, when we don’t digest foods, the bacteria in the our gut digest them for use. When they do, as a byproduct they make gases. This is why people who are lactose intolerant can experience extreme gas and bloating, as well as diarrhea, if they venture down the dairy path.

There are a number of other constituents that can possibly fall into the non-toxic category. Some individuals can have symptoms when consuming these. Vasoactive amines, like histamine, can alter blood vessel permeability and cause digestive upset. Certain food colourings, like yellow die #5 (tartrazine), are known for causing asthma in certain individuals. Monosodium glutamate (sometimes going by the name yeast extract) can cause neurological symptoms like migraines.

Navigating the World of Food Reactions

With all of the different types of food reactions, it’s important to take a systematic approach to determine what might be affecting you. Finding the culprits using food journals, lab testing, and elimination diets, are the best way for preventing symptoms for good. Remember that each of these methods are a piece of the puzzle. They are very rarely the complete picture.