You are probably aware of food allergies: queue dramatic scene of someone (we’ll call him Bob) accidentally eating something that contains peanuts, or shellfish.

Bob sits chatting at a restaurant as his food arrives. He casually whisks a bite of food from his plate into his mouth, and seconds later he is short of breath, and a choking sound starts reverberating through the restaurant. He is having an immediate severe immune reaction, and Bob’s throat begins to swell and constrict, and his skin has an immediate immune reaction causing his skin to be bright red! The waiter yells out for a doctor, and miraculously, there’s one at the next table; epipen in hand.

End scene.

The scene with Bob is dramatic, but food allergies can absolutely be this life threatening! While food allergies are somewhat rare, food sensitivitiesare extremely common.

How is a food sensitivity different than a food allergy?

A food sensitivity is different than a food allergy. While food allergies appear very quickly (like with our poor friend Bob above), food sensitivity symptoms can take days to manifest. That’s right, that piece of bread or pizza that you ate on Monday may trigger a reaction that affects you on, or until Friday. Bummer that it wasn’t that kale you just ate, and you can’t swear to a pizza and pasta only diet, I know.

This is where it becomes difficult to find which foods are making us sick. Even though the most common food sensitivities are bad foods, some people can have food sensitivities to “health foods.” Food sensitivity symptoms can be varied and seemingly unrelated, such as:

  • Brain fog
  • Headaches or migraines
  • Joint pain
  • Abdominal pain
  • Skin issues like rashes or eczema
  • Fatigue
  • Constipation
  • Weight gain

The immune system

The immune system’s role is to protect us from the outside world. Parasites, toxins, mold, viruses, bacteria: you name it, the immune system will try it’s best to defend the body. At some point, the immune system may be over-zealous in its job. In order to protect the body, the immune system may mistakenly attack food proteins that enter the body. Some of the foods may look sinister(gluten or dairy), and some may be an innocent bystander (broccoli). Most of the immune system’s cells (around 80%) either reside or travel through the gut. When the gut becomes porous, this exposes the immune system, exposing and engaging the immune system (not in a good way).

What is leaky gut?

Leaky gut is a condition in which the single-cell layer of gut cells separates. Think of your gut cells like children playing red rover, held together by tight junctions (arms). With leaky gut, or intestinal permeability, the red rover players have let go, and now food particles, bacteria, and many other objects can pass directly into the body, bypassing the body’s natural defense mechanism. Leaky gut can be considered the basis of many diseases, due to the fact that it stimulates the immune system continuously, while also creating large amounts of inflammation.

While it is important to find out which foods are causing trouble, the ultimate goal is to fix the reason for food sensitivities in the first place.

Why do I have food sensitivities?

Many things can cause the gut and immune system to be off-kilter. Including:

Breakdown in digestion

When the body cannot breakdown and digest foods, the gut lining can become irritated. Your stomach, gallbladder, pancreas, and small intestine play a delicate symphony in order to extract all that we need from our food, while getting rid of the waste. When there is any alteration in digestion at all (from stress, medications like Proton-Pump inhibitors, NSAIDS, too much or too little exercise, or increasing age), we can’t absorb all the nutrients we need, and the gut has to work harder to absorb as much as possible.


Infections in the gut are one of the most important, yet overlooked, keys to our health. Many people can have chronic gut infections for years or decades and never know the root of their health concerns. Certain infections like h. Pylori, parasites, candida, SIBO, and other pathogenic bacteria can rob our body of nutrients. They also damage the gut and create enormous amounts of GI inflammation. When the gut is inflamed from infections, the immune system is activated; therefore, more diligently looking for foreign invaders. Note- you don’t have to have GI symptoms to have GI infections*


Up to 80% of the immune system’s cells are located within the gut. When the immune system detects invaders, it will sound an alarm of inflammation all over the body in order to stop, or degrade the invasion. Many people have chronic, widespread inflammation stemming from their gut.

Bacterial imbalance

The gut is host to about 100 trillion bacteria. There are thousands of different families and all must be in good balance for proper metabolism, good mood, robust immune function, digestion, and overall health. When bad bacteria begin to overgrow, the terrain of the gut is changed, like weeds taking over a garden. This can stimulate an immune response and damage the gut, leading to food sensitivities.


There have been over 80,000 toxins introduced to our environment since WW2. Most of the toxins have not been properly tested to see how they react in humans long term, and none have been tested to see how they react with one-another long term. When the body cannot properly detoxify the harmful substances, they build up in the body, and can cause chronic immune system activation.

Supplements to aid

When digestion is lacking, certain supplements can be introduced to help break down food. HCL is commonly used to help the stomach in producing more acid in order to break down foods, especially proteins. Broad-spectrum enzymes such as lipase, amylase, and protein aid the pancreas in breaking down food in the small intestine. The gallbladder can also be helped by supplements than can thin the bile, allowing it to flow freely to break down fats.


Glutamine is an amino acid that is the primary fuel for enterocytes (intestinal cells). When under stress or inflammation, glutamine can be pulled away from the gut, leaving the intestines without their primary fuel source.


Colostrum powder contains immunoglobulins, proline-rich polypeptides (PRPs), growth factors, and vitamins and minerals to support a robust and balanced immune system.


Collagen protein contains amino acids such as glycine and proline; which are essential for repairing damaged gut lining. Collagen protein also has benefits for the skin ,hair, and nails.


Anti-inflammatory herbs likes turmeric, ginger, DGL, and boswellia can be beneficial in reducing inflammation in the gut. You can put them on food, use in a smoothie or tea, or take as a supplement.


Probiotics have been shown to be powerful in decreasing inflammation in the gut, crowding out bad bacteria, and setting the stage for good bacteria to grow and proliferate.

Food sensitivity testing

If you have gone to your doctor and asked for a food allergy panel, you may have had an IgE panel ran. This food allergy blood test checks for immediate food allergies (peanut, shellfish, etc.). A well-informed Functional Medicine practitioner may run food sensitivity blood tests such as IgA and IgG response to different foods. Immunoglobulins are antibodies that the immune system uses to mark and take out foreign invaders. Immunoglobulin A (IgA) are mainly concentrated in mucous membranes such as the gut. Immunoglobulin G (IgG) are more widespread and more prevalent, traveling all over the body. When there are antibodies present to certain foods, it means that the immune system has deemed them as foreign and is attempting to mount a response against it. That in turn leads to inflammation and damage across different body systems.

If you don’t have access to food sensitivity testing, and you are still working on cleaning up the gut, an elimination diet may be a sufficient start to begin healing the gut and calming the immune system. An elimination diet consists of eliminating certain foods for a period of time, and then re-introducing foods one a time to see if symptoms return or flare. For example, elimination diets need to last for at least 8 weeks, but sometimes longer depending on the condition. After the initial period of elimination, foods are introduced back one at a time in order to see if they irritate the gut or immune system.

Top Food Sensitivities:

  • Gluten (bread, pasta, pizza, crackers, cookies, cake, soy sauce, many other sources)
  • Dairy (milk, cheese, butter, yogurt, sour cream, yogurt)
  • Soy (soy protein, tofu)
  • Eggs
  • Corn (corn oil, high fructose corn syrup, chips, processed foods)
  • Peanuts
  • Sugar
  • Nightshades (peppers, tomatoes, potatoes, eggplant)

*Caveat – You must eliminate the foods completely. You can’t cheat every day, or every few days, and still heal the gut. It’s like having 10 nails in your foot- if you take 1 or 2 out for awhile, will you feel better? Probably not. If you take all 10 nails out, give your foot a chance to heal and regenerate, then introduce 1 by 1- you are better able to see which nails (foods) are harmful to the body.

Food sensitivities can be chronic and damaging to your gut, immune system, and to your health in general. If you or someone you know is struggling with a chronic disease, it would be critical to switch up the diet in order to achieve true wellness.