In this post I will discuss food “sensitivities”, “intolerances”, and other adverse food reactions. We will discuss how they are similar and how they are different, as well as how to identify each one. This is a complex area to try to navigate, but I hope that my article can at least help you understand the basics of the possible reactions we can have to our food.

Most of the time the terms “food sensitivity” and “food intolerance” are used interchangeably, but they are not the same thing. Here’s a blow-by-blow of how the different adverse food reactions differ!

Two main categories-

  1. Immediate reactions happen quickly- usually within seconds or a few minutes. Most often these reactions will have something to do with the mouth, tongue, or throat.

  2. Delayed reactions can take anywhere from a few minutes to a few days to fully manifest, making them notoriously difficult to track.

Immediate reactions-

  1. Food allergies happen when the immune system makes IgE antibodies against a part of a food (ex: peanuts)

  2. Other quick reactions that don’t have an IgE component are generally caused by a histamine response. This is still immunologically related to true allergies, since it is typically the same types of cells causing the reaction.

Delayed reactions-

  1. If you make antibodies to foods in this category it is typically not IgE (IgG, IgA). Oftentimes being in this category means that you have autoimmunity and leaky gut syndrome (or at least are more prone to those things).

  2. If you don’t make antibodies to your food then it is an “intolerance“. This usually means that the food is causing inflammation (immune activation without antibodies directly against that food) or it is not being digested properly.

Delayed Non-IgE Reactions-

  1. Celiac disease is an autoimmune disease where your immune system is trying to destroy two things: gluten and your own intestine. It is not uncommon for Celiacs to have other autoimmune reactions/diseases AND other food sensitivities.

  2. Food sensitivities are antibody mediated reactions other than Celiac disease. This includes non-Celiac gluten sensitivity. Food sensitivity testing (like Cyrex) would be helpful in identifying these reactions.

Please note that BOTH of these groups of people need to be very strict in their dietary avoidance of an antigen. This is because these people almost always have an autoimmune component to their problem, whether or not it’s been formally diagnosed as such. Even a little bit of gluten or another antigen is enough to spark an immune reaction and autoimmune tissue destruction.

Delayed Reactions Without Antibodies-

  1. If your bugs aren’t digesting your food properly you’ll definitely feel the consequences!

    1. If you have a FODMAP or fiber intolerance it likely means you have an overgrowth of bacteria in your small intestine (SIBO). Since the small intestine was never built to hold bacteria and their gases, feeding the bacteria causes gas, bloating, and other GI distress (IBS). The best test available for SIBO is a breath test.

    2. Your gut bugs play a large role in digesting (or not digesting) things like histamine and oxalate.

  2. If you can’t digest or metabolize your food properly (note- those are two separate things) that can cause trouble, too. This is not a complete list, but it’s at least a start. Oftentimes folks in this category can “bandaid” their problem by taking extra digestive enzymes, vitamins, or probiotics. Some of these can have a genetic component to them, so something like 23 And Me can be helpful.

    1. Oxalate

    2. Sulfur

    3. Histamine

    4. Lactose (lactose intolerance)

    5. Fructose

    6. Large proteins (ex: gluten intolerance)

  3. You can create inflammation with a number of foods and food ingredients. Some compounds like phytohemagglutinin/lectin in beans actually turn on T cells and can induce inflammation by immune activation. Others make your food harder to process (dye), mess with your gut buys (pesticides), or induce other types of inflammation (MSG).

    1. Food dye

    2. Artificial sweeteners

    3. MSG

    4. Lectins (in beans)

    5. Preservatives

    6. Pesticides

I hope you found this diagram and article helpful. If you think you need help navigating your health issues, please call my office in Chapel Hill, NC at 919-238-4094.

In health,

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