Migraine
Confused about food sensitivity testing?
by Kate Whimster, BCom, MIFHI, ND
This subject is covered in a past post What's the difference between food sensitivity, allergy, or intolerance?, but given the recent media attention on food sensitivity testing I wanted to provide a pro/con (in this case beginning with the “con” side) summary for anyone who might have questions. Then I’ll explain how I look at food sensitivities in my practice.
Question: Is there value to food sensitivity testing?
Con:
There has been a lot of media coverage in response to an article (unfortunately you need to be CMAJ member for full access) by Dr. Elana Lavine in the Canadian Medical Association Journal criticizing food sensitivity testing.
Pro:
There are several counter-arguments to be made to Dr. Lavine’s assertions:
Contrary to what Dr. Lavine asserts, there is research evidence for the use of food sensitivity testing:
Here is a good, succinct rebuttal from Dr. Elaine Chin and here is a press release from the Ontario Association of Naturopathic Doctors.
My thoughts:
In my practice, food sensitivity testing is not my first choice for treatment, but I have used it in certain circumstances. Here are some key points I consider:
This subject is covered in a past post What's the difference between food sensitivity, allergy, or intolerance?, but given the recent media attention on food sensitivity testing I wanted to provide a pro/con (in this case beginning with the “con” side) summary for anyone who might have questions. Then I’ll explain how I look at food sensitivities in my practice.
Question: Is there value to food sensitivity testing?
Con:
There has been a lot of media coverage in response to an article (unfortunately you need to be CMAJ member for full access) by Dr. Elana Lavine in the Canadian Medical Association Journal criticizing food sensitivity testing.
- Here is an article from the Globe and Mail: Tests for food allergies, sensitivities a ‘waste of money,’ doctor says
- And here is a video with a bit of a more balanced perspective from the CBC: Food sensitivity tests
Pro:
There are several counter-arguments to be made to Dr. Lavine’s assertions:
- IgE testing (for food allergy) and IgG testing (for food sensitivities) are different things. For a great comparison, here is a presentation from Rocky Mountain Analytical, one provider of food sensitivity testing. For a good summary, check out the chart on slide 11.
- A skin-prick test, while considered the gold standard “allergy” test, is not a method that tests your response to food in the way you are actually exposed to food. You don’t eat through your skin, you interact with food via your digestive tract. And the response that your body makes to food can be an IgE response (quick, itchy, clear cause and effect) or an IgG response (delayed, vague symptoms, difficult to identify cause).
- Only a medical professional (naturopathic doctor ideally or a medical doctor well-versed in nutrition) can understand how to best administer the test to get the most useful results and use this information for effective treatment.
Contrary to what Dr. Lavine asserts, there is research evidence for the use of food sensitivity testing:
- This article summarizes some research on IgG allergy testing
- Food-specific serum IgG4 and IgE titers to common food antigens in irritable bowel syndrome
- Diet restriction in migraine, based on IgG against foods: a clinical double-blind, randomised, cross-over trial
- Serum IgG responses to food antigens in the italian population evaluated by highly sensitive and specific ELISA test
- Specific humoral response to cows' milk proteins and ovalbumin in children with atopic dermatitis
- Treating irritable bowel syndrome with a food elimination diet followed by food challenge and probiotics
- A critical review of IgG immunoglobulins and food allergy implications in systemic health
- I’m sure there is even more to be found - check out PubMed if you are interested.
Here is a good, succinct rebuttal from Dr. Elaine Chin and here is a press release from the Ontario Association of Naturopathic Doctors.
My thoughts:
In my practice, food sensitivity testing is not my first choice for treatment, but I have used it in certain circumstances. Here are some key points I consider:
- The test measures only one point in time. Human beings, however, are constantly adapting and changing. At the time of testing, results indicate a particular response to foods. But how might these responses change as your immune system is balanced such that it does not react to substances that are not harmful? I see changes in immune response all the time, most commonly when I treat seasonal allergies. I’ve treated patients who have progressed from constant anti-histamine usage (that was still not controlling symptoms) one year to nearly no symptoms and no need for medication the next.
- Nutrition is a major part of my treatment with most patients. My approach to nutrition is that there are no “bad” foods, just foods that work well for you (the patient) and others that don’t fuel your body in the best way to achieve optimal wellness. I look to personalized nutrition to identify what the best nutritional approach will be for each individual.
- There are several health concerns that warrant investigation into food sensitivities, such as: most digestive concerns (IBS, constipation, diarrhea, acid reflux), asthma, migraines, chronic fatigue, fibromyalgia, allergy symptoms, skin issues (eczema, psoriasis, acne), arthritis), failure to thrive, and more. The question is, what is the best way to determine foods that may contribute to these conditions?
- Before testing, I encourage patients to do an elimination diet, which is considered the gold standard for identifying foods that may be contributing to symptoms. This approach is both diagnosis and treatment at once: patients usually experience a significant reduction in symptoms while in the elimination phase (confirming that eliminated foods contribute), they immediately begin to alter habits (perhaps the most challenging aspects of naturopathic treatment), and they gain firsthand experience of how foods affect them during the reintroduction phase.
- However, some patients prefer more objective information via a lab test and find this more motivating for changing habits. Also, some patients may find the elimination diet very challenging and would prefer a more focused elimination diet based on lab results. In either of these cases, it is important to use the test results as a guide and symptoms as feedback to determine if the treatment approach is effective.
- In the case of gluten sensitivity, I also find lab results more motivating for patients, since 100% avoidance of gluten can be challenging and having “hard data” as well as other lab results to monitor (one example would be anti-thyroid antibodies) can help ensure higher compliance and therefore improved outcomes.
Comments
What's the difference between food sensitivity, allergy, or intolerance?
by Kate Whimster, BCom, MIFHI, ND co-authored with Mélanie DesChâtelets, ND.
Do you ever feel confused about the difference between food sensitivity, food allergy and food intolerance? The differences are actually pretty simple to understand and will help you understand how food affects you. First, some basic definitions:
Antibody: A large Y-shaped protein produced by the immune system. Its job is to recognize foreign proteins and neutralize them. It’s what happens when you get a cold, the bacteria or virus is recognized and then neutralized by antibodies.
Enzyme: In simple terms enzymes help breakdown things. Enzymes are very specific for what they break down. Therefore, your body has thousands of different enzymes to break down very specific compounds. Without enzymes the process may not occur at all or at a very reduced rate. In the digestive system, enzymes help break down food into smaller units for absorption.
Both food allergy and food sensitivity are antibody-mediated reactions to food. The antibody recognizes a food protein as harmful and tries to neutralize it. If this is similar then what is different? We have different types of antibodies in our body. Different types of antibodies react differently and cause different symptoms.
Food allergy
Food allergy is mediated by an antibody called IgE. When this type of antibody reacts with a foreign protein it immediately elicits typical reactions ranging from uncomfortable to life threatening. Skin irritation, redness, and swelling are common. Difficulty breathing is more disturbing as it represents tightening of the airway. Other symptoms such as hoarseness of voice, stuffy and runny nose, itchy and red eyes as well as nausea and vomiting can are also seen with food allergies.
Here’s a diagram to demonstrate - imagine the pink line represents the symptom threshold; when you cross this line you have symptoms. The star represents the ingestion of the allergic food item.
With food allergy, as soon as the offending food is ingested, IgE levels rise and react quickly. The allergic symptom threshold is always reached. Avoidance of this offending food is necessary as it can be life threatening. The levels of IgE will also drop relatively quickly and within 5-7 days you typically no longer have symptoms.
Food sensitivity
Food sensitivity is mediated by an antibody called IgG. IgG antibodies react very differently from IgE. When IgG antibodies react with foreign proteins, they elicit a milder, slower, and non-typical reaction. Symptoms can vary from migraines, to increased behavioural difficulties in children with ADHD, to chronic digestive concerns (constipation, diarrhea, IBS, IBD), decreases in energy, skin issues (acne, eczema), and other vague symptoms. Here’s the problem - unlike food allergies, food sensitivities are very hard to diagnose. This is because their impacts can be seen 24 to 48 hours after the ingestion of the offending food. There are two ways that can help identify food sensitivities: the first is a strategic elimination/hypoallergenic diet, which works as both a diagnostic tool (to identify offending foods) and treatment (avoidance of offending foods as a first step towards long-term healing). The other is an IgG food sensitivity blood test - I offer this testing via either Immunolabs or Rocky Mountain Analytical. This tests how reactive your IgG antibodies are against various foods. The higher the reactivity the higher likelihood a food sensitivity might be present. This test can be a good starting point in assessing potential food sensitivity.
Here’s a diagram to demonstrate how IgG works.
With food sensitivity, the offending food is ingested and the IgG antibody levels rise slowly and linger for up to 3 weeks. This is what makes a food sensitivity so hard to diagnose. You first ingest the offending food sensitivity and you are symptom-free. This is because you are still far from your symptomatic threshold. In a few days you ingest this same food item and again no symptoms. What you don’t know is that your IgG antibody levels have accumulated with those of your last exposure. Third time is a charm, you ingest the food and this time you get symptoms, such as migraine, constipation, weight gain, water retention, skin breakouts, fatigue, etc. Please note in this example I used 3 days but this is for illustrative purposes and is not literal. It can be confusing! Symptoms don’t appear immediately, so it is hard to link exposure to symptoms and you are left guessing at which foods is causing symptoms. Unlike an IgE food allergy were every single exposure is followed by symptoms, IgG food sensitivities depends on frequency and dose of the exposure.
Food intolerance
Food intolerance represents an enzyme deficiency, meaning your body can’t break down a component of food and this causes digestive upset. The most obvious example is lactose intolerance or lactase enzyme deficiency. This enzyme is important in breaking down lactose found in dairy products. The lack of this enzymes results in gas, diarrhea, and discomfort.
I work with many patients to address food sensitivities. The goal is not to eliminate a food for the rest of your life although avoidance for a period of time is sometimes necessary while we improve the integrity of the gut lining so that you can once again tolerate the offending food. When you figure out which foods you are sensitive to and understand the symptoms, you are empowered to take charge of your health!
Do you ever feel confused about the difference between food sensitivity, food allergy and food intolerance? The differences are actually pretty simple to understand and will help you understand how food affects you. First, some basic definitions:
Antibody: A large Y-shaped protein produced by the immune system. Its job is to recognize foreign proteins and neutralize them. It’s what happens when you get a cold, the bacteria or virus is recognized and then neutralized by antibodies.
Enzyme: In simple terms enzymes help breakdown things. Enzymes are very specific for what they break down. Therefore, your body has thousands of different enzymes to break down very specific compounds. Without enzymes the process may not occur at all or at a very reduced rate. In the digestive system, enzymes help break down food into smaller units for absorption.
Both food allergy and food sensitivity are antibody-mediated reactions to food. The antibody recognizes a food protein as harmful and tries to neutralize it. If this is similar then what is different? We have different types of antibodies in our body. Different types of antibodies react differently and cause different symptoms.
Food allergy
Food allergy is mediated by an antibody called IgE. When this type of antibody reacts with a foreign protein it immediately elicits typical reactions ranging from uncomfortable to life threatening. Skin irritation, redness, and swelling are common. Difficulty breathing is more disturbing as it represents tightening of the airway. Other symptoms such as hoarseness of voice, stuffy and runny nose, itchy and red eyes as well as nausea and vomiting can are also seen with food allergies.
With food allergy, as soon as the offending food is ingested, IgE levels rise and react quickly. The allergic symptom threshold is always reached. Avoidance of this offending food is necessary as it can be life threatening. The levels of IgE will also drop relatively quickly and within 5-7 days you typically no longer have symptoms.
Food sensitivity
Food sensitivity is mediated by an antibody called IgG. IgG antibodies react very differently from IgE. When IgG antibodies react with foreign proteins, they elicit a milder, slower, and non-typical reaction. Symptoms can vary from migraines, to increased behavioural difficulties in children with ADHD, to chronic digestive concerns (constipation, diarrhea, IBS, IBD), decreases in energy, skin issues (acne, eczema), and other vague symptoms. Here’s the problem - unlike food allergies, food sensitivities are very hard to diagnose. This is because their impacts can be seen 24 to 48 hours after the ingestion of the offending food. There are two ways that can help identify food sensitivities: the first is a strategic elimination/hypoallergenic diet, which works as both a diagnostic tool (to identify offending foods) and treatment (avoidance of offending foods as a first step towards long-term healing). The other is an IgG food sensitivity blood test - I offer this testing via either Immunolabs or Rocky Mountain Analytical. This tests how reactive your IgG antibodies are against various foods. The higher the reactivity the higher likelihood a food sensitivity might be present. This test can be a good starting point in assessing potential food sensitivity.
With food sensitivity, the offending food is ingested and the IgG antibody levels rise slowly and linger for up to 3 weeks. This is what makes a food sensitivity so hard to diagnose. You first ingest the offending food sensitivity and you are symptom-free. This is because you are still far from your symptomatic threshold. In a few days you ingest this same food item and again no symptoms. What you don’t know is that your IgG antibody levels have accumulated with those of your last exposure. Third time is a charm, you ingest the food and this time you get symptoms, such as migraine, constipation, weight gain, water retention, skin breakouts, fatigue, etc. Please note in this example I used 3 days but this is for illustrative purposes and is not literal. It can be confusing! Symptoms don’t appear immediately, so it is hard to link exposure to symptoms and you are left guessing at which foods is causing symptoms. Unlike an IgE food allergy were every single exposure is followed by symptoms, IgG food sensitivities depends on frequency and dose of the exposure.
Food intolerance
I work with many patients to address food sensitivities. The goal is not to eliminate a food for the rest of your life although avoidance for a period of time is sometimes necessary while we improve the integrity of the gut lining so that you can once again tolerate the offending food. When you figure out which foods you are sensitive to and understand the symptoms, you are empowered to take charge of your health!
