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The Difference Between Food Allergies And Intolerances

Food Allergies And Intolerances

Food intolerance testing has become a popularly marketed test within the health and nutrition world, particularly with all the hype over gluten-free foods and the common gluten intolerances these days. Whether you want to know if you’re sensitive to gluten, dairy or a random fruit like pineapple, lots of people now opt for that oral test where they take a sample from your saliva and test for your personal intolerances.

Food “Intolerance/sensitivity” is different than a food allergy or allergy testing (the test where the doctor sticks certain needles in your back or on your forearm to determine a histamine/inflammatory response). Let’s first determine the difference between an Intolerance and an Allergy.

Food Allergies And Intolerances


A “food Intolerance” or “sensitivity” is an inflammatory reaction to a particular food that often manifests subtly, or chronically which causes inflammation. Believe it or not this could be the reason behind those mysterious headaches you have been getting, skin breakouts, gut issues and so on. Having said that, you need to be aware that it is different to an acute inflammatory response (i.e. sudden loose stools, hives, closed throat, swollen eyes, etc.); the latter is an allergy.


A food allergy is the result of your body’s immune system attacking the protein present in a certain food. Your body releases powerful immune chemicals (like histamine) as a result of a food allergen entering your bloodstream. These chemicals cause many symptoms such as swelling, headaches, eczema, indigestion and so on. It is important to be aware that the top 8 most common food allergies are milk, eggs, fish, shellfish, soy, wheat, peanuts and tree nuts (note that peanuts fall under the umbrella of a legume, and tree nuts such as almonds, cashews, hazelnuts, brazil nuts arehard-shelled nuts).


Types of Food Intolerances

Several common food intolerances include:

  1. Lactose intolerance. Usually caused by a deficiency in Lactase – the enzyme responsible to digest Lactose (a type of sugar found in dairy products). Also – just to clarify; its not the same as milk sensitivity.
  2. Gluten sensitivity. Gluten is a protein found in the grains wheat, barley, and rye. In some people, consumption of these grains leads to celiac disease, which is an autoimmune condition (not a food allergy or a food intolerance). In other people, ingesting grains seem to cause symptoms of food intolerance as opposed to celiac patients who suffer from intestinal damage. The only current treatment for gluten sensitivity is avoiding all gluten- containing grains. Avoiding allergy-causing foods, this can involve carefully reading labels on packaged goods.
  3. Histamine intolerance. Histamine is a chemical that is naturally found in aged foods, such as cheeses, and smoked or preserved meats and certain wines. People who are sensitive to histamine-containing foods can suffer from stomach pain, diarrhea, skin rash. Because food intolerance and food allergy overlap in

symptoms, it can be difficult to make the proper diagnosis. Since every human body is different, these reactions can vary from person to person. Maybe you develop a rash after eating shrimp, experience migraines every couple of days, or get bloated and uncomfortable after you drink a skinny latte.


Food Allergies And Intolerances


How can you determine the difference between a food allergy, food sensitivity, or food intolerance?

I believe an elimination diet is the best way to determine what food is causing the intolerance, and then avoid the food that are creating the sensitivities. Doctors may also conduct blood tests to measure the antibodies or IgE levels in the blood, which require a skin prick testing to identify any food allergies. There are multiple ways to diagnose a food allergy. Skin Prick Test: This test done in a doctor’s office, pricks a tiny amount of various food proteins and awaits response from your skin indicating an allergic response (i.e. a flare formation causing redness and swelling).


IgE: This is a blood test, designed to detect IgE antibodies in response to various food proteins. Food Challenge: a dose of food protein vs placebo is given at 20-minute intervals while waiting for signs/symptoms of food allergy. However, this test is not common because there is a risk of a severe reaction.

Unlike allergies, food sensitivity reactions may not occur right away and can happen up to 72 hours after consumption.  This is why it is SO hard to determine what may be causing your symptoms by only doing a typical elimination diet. The food that may be triggering your eczema, for example, may be something that you ate nearly two days ago!


Food Allergies And Intolerances


Now the good new is food sensitivities are typically not permanent, and once the gut is healed, the negative response may decrease. Many people can eventually resume eating some of the foods they were once sensitive to, even if only in small doses. Over time, food sensitivity reactions may change, depending on lifestyle, diet, medications etc.

You can treat intolerances by avoiding the food you are sensitive to, taking appropriate digestive enzymes to help digest the food. Again – an elimination diet is the best way to go about this mystery and really rule out what is giving you this distress.


Zein Nimri is an AFPA certified sports nutritionist, NESTA kids nutritionist, long distance runner, cyclist and traveller with big dreams. Follow her on Instagram @Zeinutritionist she is currently an Eating Disorder Recovery Coach.