A common misconception about food sensitivities is that symptoms of indigestion must be involved one way or another. This is not always the case, however, and in my practice it’s much more common for me to see food reactions in places other than the gut. Symptoms of indigestions are just one of many ways the body can respond negatively to food.

What kinds of food reactions can you have? What are common signs of food reactions that are found outside of the gut? How do you reduce reactions to food?

Different types of food reactions

Food sensitivity is a generic term used to describe multiple types of reactions our bodies can have to food. Enzyme deficiency is one common type of food sensitivity. For example those of us with lactose intolerance are deficient in the enzyme lactase. As a result when we consume lactose in milk or ice cream, the lactose isn’t broken down properly, leading to gas, bloating, abdominal discomfort and/or bowel changes – symptoms vary from mild to severe.

Other food sensitivities can involve the immune system. It’s no accident that 70% of our immune system resides along our digestive tract and microbiome. Every day, compounds enter the gut from the outside world and our immune system diligently monitors and responds to potential threats. Like the different departments of the military, the immune system has different “departments” each carrying out different immune reactions. Some reactions happen locally in the gut and others are via antibodies that travel through the bloodstream to other parts of the body.

Immediate/Food Allergies: The most well-known of these immune reactions is food allergies. We typically use the term “allergies” to describe immediate immune reactions to a specific type of food(or environmental compound). In these cases, the body has antibodies that “remember” these allergens from previous exposures and upon subsequent exposure, triggers fast, and sometimes dramatic body reactions. Because these reactions can impact the ability to breathe, it’s important to identify (and avoid) your food allergens. If you’ve had a skin prick test at an allergist’s office, you were likely tested for these immediate or “IgE” reactions.

Delayed Food Sensitivities:  Other “departments” of the immune system are responsible for delayed immune reactions. These reactions involve different antibodies and trigger a slower reaction to food – hours or days later. This delay often makes it difficult to identify the link between a food trigger and symptoms.

Food Autoimmune Reactivity: Chronic health conditions have been increasingly linked to consumption of dairy and wheat. One reason may be due to molecular mimicry. Proteins in these foods are structurally similar to some human tissue (such as tissues found in a joint or around a nerve fiber). An optimal immune system will know not to attack its own tissue but trauma, shock, surgery and environmental chemicals can disrupt immune function causing the immune system to attack the problem food protein AND its own (structurally similar) tissue. This fascinating process is called molecular mimicry and helps us to understand how foods and other lifestyle factors may be contributing to the rise of autoimmune conditions.

Food reactions from suboptimal gut function/flora: You can have reactions to foods that are caused by a number of other issues such as weak stomach acid or an overgrowth of “bad” microbes in the gut. Many of these issues are affected by lifestyle factors like stress, medications, eating/fasting habits and even taste and temperature of the food. Over time these reactions can compromise the gut lining allowing partially digested food particles and microbial particles to be “leaked” into the bloodstream triggering the immune system to react. Chronic poor digestion can increase the risk of food sensitivities and chronic conditions- all without obvious indigestion symptoms!


3 Signs of food reactions outside of the gut 

Although food sensitivities involve your gut, they don’t always cause symptoms of indigestion. In fact, in my practice, I see more symptoms of food reactions outside of the gut. Here are some of the most common signs:

  1. Joint pain: Chronic joint pain and/or swelling with no known injury? Rheumatoid arthritis and other recurrent joint issues may indicate food sensitivities.

  1. Brain issues: Brain fog, difficulty concentrating, insomnia, anxiety and headaches can be related to reactions triggered by certain foods. Removing problem foods can be the missing piece when it comes to stubborn insomnia or anxiety and can reduce the frequency of migraines.

  1. Skin issues: Recurrent or chronic skin problems from eczema to hives can be related to a number of different food reactions.


The foods we eat – including how we digest it – have a profound effect on our health. That’s why in naturopathic medicine we assess gut function in almost everyone – even if indigestion is not your main concern.

To get more out of your food and supplements and better tolerate a wide variety of foods, incorporate 3 of my favourite, simple (and profound) steps for improving digestion and energy.

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