Food Allergies Versus Food Intolerances

Food Allergies, Intolerances, and Sensitivities


Chances are you or somebody you know has a food allergy. Or, maybe it’s a food intolerance? Is it a sensitivity? Did you know that there is a difference? All three of these terms are often used interchangeably, but there are important differences between them. When we look at them from a symptomatic perspective, food allergies affect your immune system in an immediate manner with potentially life-threatening symptoms. Food sensitivities also affect your immune system, but symptoms can be delayed and much more subtle. And, food intolerances tend to affect your digestive system only. Let’s breakdown food allergies, sensitivities, and intolerances in more detail so that you can better understand the powerful ways in which food can impact your health.

What is a Food Allergy?

Your immune system controls how your body defends itself. It is designed to identify foreign invaders in your body and launch a counterattack against them. During this process, chemical messengers are sent to eliminate the danger in the body. This is called the inflammatory response.

When a food that you are allergic to is introduced into the body, the immune system hyper-reacts and launches an immediate attack. This process can produce dangerous and acute symptoms like hives, swelling, and life-threatening anaphylaxis. Food allergies launch a direct and immediate assault on the immune system by activating the release of immunoglobulin E (IgE antibodies).

In fact, a food allergy can cause a serious or even life-threatening reaction by eating a microscopic amount, touching, or inhaling the food. When it comes to food allergies versus food intolerances, an allergy cannot be mistaken.

Common Food Allergies:


Food allergies are quite common, affecting around 5% of adults and 8% of children. And, while any food can cause an allergy, most allergies are caused by just eight foods (1):

  • FISH
  • EGGS
  • SOY

Food allergies may start in childhood or as an adult, and there is currently no cure for food allergies.

What is a Food Intolerance?

A food intolerance is different than a food allergy in many ways. First of all, it will not activate a life-threatening immune response like anaphylaxis. Food intolerances are usually caused by the body’s inability to breakdown or digest a certain food, and thus symptoms are usually limited to the digestive system.

  • Food Intolerance Digestive Symptoms:
  • Nausea
  • Stomach pain
  • Gas, cramps or bloating
  • Vomiting
  • Heartburn
  • Diarrhea

Food intolerances are usually caused by a lack of digestive enzymes needed to breackdown certain foods. The most common intolerance is lactose (the sugar found in milk). Intolerances are usually pretty identifiable because these digestive symptoms usually appear about an hour after eating the food.

Intolerances don’t activate the immune system in a direct way but can increase low-grade inflammation in the body if you continue to consume the foods to which you have an intolerance. More on this below.

🌾 A Note on Celiac Disease


It is important to note that Celiac Disease is not a food allergy or intolerance. Celiac disease is a serious autoimmune disease that occurs in genetically predisposed people where the ingestion of gluten (the protein in grains such as wheat, barley, rye) leads to damage in the small intestine. (2) Celiac is diagnosed through several types of blood tests and in many cases an intestinal biopsy is necessary.

Many people are sensitive to gluten (this is sometimes called Non-Celiac Gluten Sensitivity or NCGS), but consuming the protein does not cause injury to the intestine. More on sensitivities and gluten below.

What is a Food Sensitivity?

Food sensitivities can be more difficult to detect. They are more subtle in the way they affect the body. In fact, sometimes symptoms will not show for a couple of hours to even days after eating a certain food.

A food sensitivity is also similar to a food allergy in that the immune system is involved. However, a food sensitivity is caused by Immunoglobulin G (IgG) and Immunoglobulin A (IgA) instead of the serious IgE-mediated reaction in a true food allergy. Food sensitivity reactions are less severe and much more delayed than a food allergy.

The terms sensitivity and intolerance are sometimes used interchangeably. This is usually just to differentiate between them and true food allergies. However, there are differences. They can both produce digestive symptoms like those mentioned above, and the can both indirectly affect the immune system through low-grade inflammation. Food sensitivities, however, can produce more subtle and delayed symptoms.

More Subtle/Delayed Food Sensitivity Symptoms:

  • Headaches/Migraines
  • Nervousness
  • Irritability
  • Depression
  • Skin Issues
  • Chronic Fatigue
  • Joint Pain
  • Hormonal/Menstrual Changes
  • Sinus Issues
  • Weight Gain & more

Most people do not usually associate the above symptoms with a food that they\’ve eaten, but a food sensitivity can cause all of them and more.

What Causes Food Sensitivities?

Food sensitivities can be caused by a lack of digestive enzymes needed to break down certain foods. They can also be caused by a lack of diversity in our diets. In fact, many of the packaged foods on your grocery store shelves are made with the same five ingredients. This has an effect on the diversity of microbiota in the gut. A lack of diversity in our guts can lead to inflammation, which affects the gut lining. When our guts become permeable or “leaky,” certain foods pass through the intestine and into the bloodstream. This activates an immune response in the body that can lead to all of the abovementioned symptoms.

It’s not only lack of diversity that can affect gut permeability. Overusage of medications and chronic stress can also affect the integrity of our intestines, which lead to food sensitivities and illnesses like asthma, chronic fatigue, eczema and so much more.

Vibrant Spore IG is a spore-based, broad-spectrum probiotic formula designed to promote a healthy gut microflora, protect mucosal integrity, and relieve small intestinal bacterial overgrowth (SIBO). Uniquely included in this formula are serum-derived bovine immunoglobulins (IgG) that bind to and eliminate microbes and toxins that are common in SIBO. Buy Now!

How to Test for Food Allergies, Intolerances, and Sensitivities:

There are many different allergy and sensitivity tests out there that help you understand which foods should be avoided from your personal diet. However, it is very important to choose the correct one. As I mentioned above, there are many different immune responses involved with allergenic foods. Therefore, there are different tests appropriate for each.

At Tringali Vibrant Health, we run the following Food Allergies, Intolerances, and Sensitivities testing:

  • IgE (immunoglobulin E) Test that measures the blood level of IgE, one of the five subclasses of antibodies. Antibodies are proteins made by the immune system that attack antigens such as bacteria, viruses, and allergens.They can become confused or cross-reactive and begin attacking foods instead. High titers of IgE are associated with allergic reactions, which is when the immune system overreacts to environmental antigens such as pollen, pet dander, and/or parasitic infections.
  • IgG (immunoglobulin G, total) are antibodies that provide long-term resistance to infections and have a much longer half-life than an IgE allergy. Because food sensitivities can present at such varied times, it is hard to isolate from a diet history alone, and testing becomes particularly useful. The degree and severity of symptoms vary greatly from person to person because of genetic makeup. The complete elimination of IgG positive foods may bring about important improvements in symptoms of irritable bowel syndrome, autism, ADHD, cystic fibrosis, rheumatoid arthritis, and epilepsy, as demonstrated in numerous clinical studies. It is important to get tested for food sensitivities to know what foods work for the patient’s body and what foods don’t. If you are only looking at allergies, or IgE, then you would miss the IgG mediated symptoms, creating an incomplete patient picture.
  • C3 (complement component 3) is a protein of the innate immune system that is activated by microorganisms in the absence of an antibody. When C3d is activated in response to an antigen, the C3 portion attaches to the antigen. This activation, even though it is independent, will amplify the reaction that occurs with total IgG greatly increasing inflammation and symptoms of sensitivity. This same reaction that was designed to amplify inflammation to microorganisms, can be triggered in response to foods. If complement is present, it will amplify an IgG reaction as much as 1000 to 10,000-fold. Therefore, tests that only measure IgG may miss the reactions to foods that are most clinically relevant. C3 will be cleaved into multiple C3 breakdown products, and all of these play a role in increasing inflammatory response to foods. 
  • IGG4 (IMMUNOGLOBULIN G SUBTYPE 4): is another antibody produced in the body to fight infection.  Desensitization injections, or allergy therapies, increase IgG4 to help neutralize the reaction of IgE. This is because of its potential to decrease histamine responses by blocking IgE from attaching to receptors, causing degranulation. Levels of IgG4 are beneficial up to a point, as they block IgE or allergic reactions and result in immune tolerance to foods.  

Using an Elimination Diet to Diagnose Food Allergies, Intolerances, and Sensitivities

By eliminating specific trigger foods such as gluten, dairy, grains, sugar, alcohol, and caffeine for a duration of time, it is possible for your body to hit the reset button on your health. This is why every single new patient at Tringali Vibrant Health is put on a 28-Day Elimination Detox Diet. After following this elimination diet for a certain period of time, you can then strategically add foods back in to see how your body tolerates them.

Book a consult with a Tringali Vibrant Health Practitioner today, or call us to learn more about our elimination diet:



The Final Word on Food Allergies, Intolerances, and Sensitivities

When it comes to which foods our bodies can process, everybody and every BODY is different. What works for your spouse, your best friend, and neighbor may not work for you. You are probably already well aware if you have a food allergy. But, if you are experiencing severe bloating or diarrhea after eating dairy, you may not know that you have a lactose intolerance. And, you may think your exhaustion or eczema is condition outside and above of what you’re eating. But, you could very well have a sneaky food sensitivity.

The good news is that many people experience vast improvements in the way that they feel after identifying intolerances and sensitivities and making real steps to removing them from their diet.

If you\’re interested in learning more about how to reach optimal, vibrant health, book a consult at Tringali Vibrant Health. Our providers can test you for food allergies, intolerances, and sensitivities, as well as other specialized testing that will have you on your way to living your best and most VIBRANT life.


Julie Vargas, APRN, FNP-BC


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About Tringali Vibrant Health

Founded by Functional Medicine Expert Elizabeth Tringali, PA-C, Tringali Vibrant Health is a Functional Medicine and Integrative Practice that looks for the root causes of your health issues to restore optimal, VIBRANT health.

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