Identifying food sensitivities is a major part of learning about our unique body. It integrates the most foundational systems in our body: the gut and immune system, therefore affecting almost every aspect of our health.

cabbage food sensitivity

IgG food sensitivity tests speed up this process by identify foods in our daily diet that may be contributing to our symptoms.

If this is your first introduction to IgG or delayed food sensitivity reactions, please see our previous article New IgG Food Sensitivity Testing at Brio to find out what IgG sensitivities are and who might benefit from testing IgG.

Here, I’ll take a moment to answer some of the most common questions we receive about this test. I hope this is helpful to those who are interested in doing the test as well as for our patients who want to gain more insight about their IgG test results.


  1. I’ve already been cutting out certain foods, like dairy, from my diet. If I have an IgG sensitivity to these foods, will it show up on my IgG test results?

If you haven’t eaten a particular food for months, you’re less likely to have antibodies to that food in your blood. This means that your test results may show a reduced reaction compared to if you had eaten the food recently. To be certain, it’s better to do the test within 2 weeks of eating the foods you wish to test, otherwise the test may not represent an accurate reactivity.

Sometimes the test shows reactivity to foods that have never been eaten. This may be due to inadvertent exposure or may be due to cross sensitivities with a related food.


  1. If my IgG test results come back showing “Elevated” reaction to certain foods, does that mean I’ll have to cut those foods out forever?

This depends on each individual’s needs and preferences. In most cases, we recommend temporarily removing foods we suspect may be contributing to symptoms. After repairing the gut, foods can be systematically reintroduced so we have a clearer understanding of how we react to the foods and in what way we want to reintroduce that into our long term diet.


  1. What are the next steps after I find out what my IgG results are?

Depending on your results, your current gut health and medical history, your doctor will work with you to determine the next steps. Often foods that show high reactivity on the test are removed from the diet for a specified duration to allow the gut and immune system to take a break while we use specific foods and nutrients to repair the gut lining.


  1. Does an IgG food sensitivity test have to be retested after some time?

For most people, this is not necessary. However, food reactivity can vary with food exposure (or lack of exposure) and overall inflammation of the gut lining (caused by food sensitivities, too much “bad bacteria”, alcohol, certain drugs, etc). So, it may be helpful for some individuals to retest IgG food sensitivities once gut health has improved.


  1. I have stomach issues. Do I have food sensitivities?

It’s important to remember that digestive symptoms can be related to multiple factors such as enzyme deficiencies, IgE allergies, stomach acid issues, too much “bad” bacteria etc. Often multiple factors are involved so a naturopathic assessment is critical to determine if food sensitivities should be suspected.


  1. I don’t have any digestive symptoms. Does that mean I don’t have any food sensitivities?

IgG or delayed food sensitivities can also cause non digestive symptoms like joint pain, migraines, weight issues and eczema. It is possible to have these symptoms without any digestive symptoms. Therefore a lack of digestive symptoms does NOT mean a lack of food sensitivities.


  1. How can I get this test done for myself or my family?
  • Current patients: Book a Return Naturopathic appointment with your naturopathic doctor
  • New patients: Book an Initial Naturopathic appointment
  • For all patients, we assess whether or not the IgG test is indicated. If indicated, usually a blood sample can be taken during that appointment


  1. How is the sample taken for this test?
  • A small blood sample is required for the test
  • In most cases, the test sample is taken during an appointment and only takes a few minutes
  • A sample can be taken by venipuncture (blood draw from a vein) or finger prick (or heel prick for infants)


  1. Is the IgG Food Sensitivity Test covered by my extended health insurance?

Some extended benefit programs cover (in part or in full) the cost of this test. Please check with your individual extended health benefits.

By first understanding each person’s unique sensitivities and nutritional needs, we then work together to repair tissue and build resilience. This is the heart of personalized nutrition. Book a naturopathic appointment to find out more about nutrition for your health.


In health,

Dr. Carin Matsushita


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