Can food intolerances cause your body’s symptoms?

 by Liesa Huppertz
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In the last decades, inflammatory diseases such as metabolic disorders, high blood pressure or heart disease, as well as degenerative processes have increased continuously. Along with them have the industrialization of food and the modern lifestyle. This leads to the questions: What causes inflammation? Does the food we eat cause inflammation? And are food intolerances causing our body to wreak havoc?

Food intolerances and inflammation are closely linked. Food intolerance is mediated by the innate immune system and leads to typical adverse reactions and inflammatory processes. To put it simple: Everything that puts stress on your body, leads to inflammation. And food intolerances are enormous stressors on your body.

So how exactly are food intolerances and inflammation linked, you may wonder. To establish this connection, we first have to look at the role of our immune system.

The role of our immune system.

Our immune system consists of three lines of defence that build on top of each other and protects us from disease.

The first line of defence consists of the surface barriers that protect us from pathogens entering our body. These surface barriers include the skin and mucous membranes. Growth of microbes on the surface is restricted by both the skin and mucous membranes releasing chemical secretion which prevents pathogens to enter the host body. Thus they cannot disrupt normal physiological functions and cause disease.

The non-specific cellular and molecular responses of the innate immune system are the second line of defence. When a pathogen has entered the host, the defences provide a rapid local response. Unfortunately, these defences don’t differentiate between different types of pathogen. So whatever enters, triggers the same way of response. The pathogen entering the body will cause swelling and reddening at the site of injury, which is called an inflammatory response. Leukocytes migrate to the sites of infection and try to engulf and destroy the foreign bodies. Immune activity within the body is regulated by antimicrobial proteins such as cytokines and complement proteins. Besides inflammation, the second line of defense includes fever (which again triggers an inflammatory response. The increased body temperature activates heat-shock proteins and suppresses microbial growth and propagation.

Finally, the third line of defense consists of lymphocytes such as B-cells and T-cells, which produce antibodies to specific antigenic fragments. The body has millions of different B-cells that are capable of detecting distinct antigens and therefore producing specific antibodies. To ensure that antibodies are only mass-produced at appropriate times, the activation of B-cells is regulated by helper-T-cells. After activation, both B- and T-cells will differentiate to form memory cells so that our body enjoys long-term immunity to a particular pathogen.

Food intolerance or allergy?

Differentiating a food intolerance from a proper allergy can sometimes be very tricky. The symptoms can often be similar, making it hard to tell an allergy from a sensitivity.

In a classic food allergy, the third line of defense of our immune system plays the key role. Your body produces antibodies known as IgE in response to certain foods that it mistakenly considers to be harmful. This is your body’s way of protecting you from the invader and in fact an inflammatory response of the immune system. The symptoms usually occur within just a few minutes and they can range from sneezing to coughing, watery eyes, skin rash, nausea or even anaphylactic shock.

Food intolerances, on the other hand, are mediated by the innate immune response, the second barrier. They are a real problem because as symptoms can take up to 72 hours to develop, we often don’t connect them with the food we ate. Thus, food sensitivities remain unrecognized in many people.

The problem with that is that when we don’t know that we hav a food sensitivity, we’ll simply continue eating the trigger food, which can inflame the gut, activate an immune response, and even cause chronic underlying inflammation. The local micro-inflammation in the intestinal tissue spreads insidiously and can manifest itself in other tissues.

So while consequences of food-induced activation of the immune system may be subtle in the beginning, they can become serious over time. Symptoms of food intolerances and resulting inflammation can manifest as anything from skin issues to chronic gastrointestinal problems, to behavioral problems, making it hard to connect them with food intolerance as the initial cause. Some common symptoms include:

  • Acne
  • Asthma
  • Chronic diarrhea
  • Headaches
  • Joint pain
  • Migraines
  • Rashes
  • Poor immune function
  • Seasonal allergies
  • Obesity
  • Irritable Bowel Syndrome

Inflamed immune system.

The problem with food intolerances is usually not the food itself, but rather our immune system’s response to it. It’s not the egg, peanut or dairy that’s toxic. The swelling, hives, redness and fever comes from your immune system mistakenly regarding them as a harmful invader.

The irony here is that your immune system is actually trying to protect you but actually causes more harm than good. It will defend you against real killers like cancer or a deadly virus, but if it misunderstands an invader - e.g. the protein from an egg or casein from milk-, your body doesn’t stand a chance.

According to an estimate, around 60% of the population suffers from an undetected food allergy. Continuing to expose your body to the trigger can lead to chronic inflammation that is associated with a whole list of chronic diseases.

Most common food intolerances.

According to estimations, more than 20% of the world’s population have a food intolerance. There seem to be certain groups of food that are more common to trigger a reaction in the body than others.

The eight most common food intolerances are:

  1. Dairy
  2. Gluten
  3. Caffeine
  4. Salicylates (natural chemicals produced by plants)
  5. Amines (produced by bacteria during fermentation)
  6. FODMAPs (fermentable oligo-, di-, monosaccharides and polyols)
  7. Sulfites (chemicals used as preservatives in food)
  8. Fructose

Most common triggers of inflammatory disease.

Essentially, every food intolerance can lead to inflammatory disorders. The most likely food intolerances though are those that cause leaky gut syndrome. These are:

  • Dairy (casein protein)
  • Gluten (gluten protein)
  • Yeast sensitivity (yeast proteins)
  • Corn allergy (zein protein)
  • Nightshade sensitivity (lectins)

When food isn’t digested properly, the partly digested proteins and sugars damage your small intestine. This leads to tiny holes in the tissue lining which allow unfamiliar protein pieces (peptides) to leak into the bloodstream. Our immune system immediately detect these foreign invaders and sets an inflammatory response in motion. And so the trouble begins. As I said, slowly at first, but over weeks or even months it builds up, until your doctor diagnoses you with a chronic disease.

How to find out your food intolerances: The elimination diet.

The elimination diet is a great tool to uncover hidden food intolerances, healing the gut, and bringing inflammation levels down.

The goal is to remove the foods that are most likely to irritate your body for a few weeks (three weeks are seen as the minimum) and up to six months to give your body a chance to calm down and focus on healing.

After a three weeks to six months you can slowly start bringing those foods back one by one in order to identify harmful foods. Try to eat the specific food every day for at least one week before reintroducing the next one.

The elimination diet can be done in different ways, starting from the length of eliminating the food to which food you actually do eliminate. Let’s get to the basic then.

The most common food allergens are:

  • Milk
  • Eggs
  • Soy
  • Fish
  • Shellfish
  • Wheat
  • Peanuts
  • Tree Nuts

In fact, those eight allergens make up for more than 90% of the food allergy reactions. Starting your elimination diet with these foods then is a good way to set things in motion.

There are also other foods that are often associated with food intolerances and therefore eliminated in the elimination diet:

  • Gluten
  • Dairy
  • Sugar
  • Legumes
  • Caffeine
  • Alcohol
  • Citrus Fruits
  • Processed Foods
  • Hydrogenated Oils

Whether you eliminate all of these foods, is up to you, but keep in mind: Many people are gluten sensitive without knowing it. Eliminating gluten may help with leaky gut syndrome which can cause allergic reactions, autoimmune reactions and high levels of inflammation.

Due to pasteurization dairy products like milk, cheese or yoghurt may lack certain enzymes which can make them potential allergens.

Allergic reactions can also be triggered by alcohol and it may increase the growth of bad bacteria in the gut.

Products like soy are huge GMO crops. Try avoiding GMO if possible and for some elimination diets eating non-GMO is a key part.

Hydronic oils may cause chronic inflammation which may lead to other food intolerances.

Whatever it is you’re eliminating from your diet, always make sure to read food labels carefully. You want to avoid even the smallest trace of the things you cut out.

During your elimination diet, it is a good idea to create and maintain a food journal. Here you want to describe how you’re feeling and your symptoms like bloating, nausea, or diarrhea on a daily basis. Hopefully, after a while, you’ll start to report improvements.

When you start to reintroduce the foods again into your diet, documenting your symptoms is an important part of the diet. You can also start to compare symptoms after cutting them out and after reintroducing them. Be prepared for some stark differences between elimination phase and reintroduction phase. These indicate which food your body tolerates and which it doesn’t.

An elimination diet certainly requires discipline. Many people don’t even realize they have an issue until they experience life without them. They think that their acne or migraine is just part of who they are when in fact it is a certain food that they just don’t tolerate. Going through an elimination diet will help you find out.


We often don’t connect our various symptoms with the food we eat since reactions are mostly delayed. Thus, immune-mediated food intolerances and inflammation are not recognized as such.

The consequences of food intolerance may be serious in the long run, even though they might feel simply annoying to you. It may lead to inflammatory conditions such as metabolic syndrome, neurological disorders, immunological comorbidities and so much more.

I cannot stress the role of food as medicine enough here. Individually tailored rotation- and elimination diets may alleviate symptoms or even restore health completely.

Dietary modification thus indeed provides a valuable, complementary therapy approach in the treatment of various inflammatory disorders.

Food intolerances and inflammation are closely linked. Whenever you eat something that your body doesn't tolerate, an inflammatory response is triggered. While inflammation every now and then doesn't hurt the body too much, you'll get a different picture if your body is constantly inflamed. Chronic inflammation is the consequence which leads to all sorts of diseases and symptoms such as migraines, rashes, asthma or poor digestion. Find out more about food intolerances and start impementing changes today!

Disclaimer: Please be aware that I am not a doctor or a medically trained person. What you're reading here is information that I researched and summarized to the best of my knowledge and processed it for your digest. Information stated on iamliesa is for educational purposes only, this information is not to replace advice from your health care practitioner. If you have any concerns about your health, always consult your general practitioner.

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