What Is Food Intolerance and Sensitivity?
A food intolerance (also called a food sensitivity) is an adverse reaction to certain substances found in food.
Unlike food allergy, food intolerance does not involve the immune system.
Rather, these substances act as irritants on the nerve endings in sensitive people.
The symptoms of food intolerance can affect four main systems of the body including:
- Nervous system: headaches, migraines, irritability, restlessness, hyperactivity
- Respiratory system: asthma, wheezing, chronic cough, sinus problems
- Gastro-intestinal tract: recurrent mouth ulcers, reflux, nausea, bloating, stomach pain and cramping, altered bowel habits
- Skin: eczema, hives, other skin rashes.
Common Triggers of Food Intolerance and Sensitivity
The most common naturally occurring substances known to trigger symptoms include:
- Salicylates: found in many fruits and vegetables, herbs and spices, honey, tea and coffee, wine and beer
- Amines: found in aged products such as ripened fruit and vegetables, cheese, wine and beer
- Glutamates: a natural flavour enhancer found in savoury foods such as cheese, mushrooms, tomatoes, grapes
- FODMAPs: poorly absorbed sugars found in a variety of fruits, vegetables, grains and dairy products
- Dairy milk protein: found in cow’s milk products such as milk, yogurt and cheese
- Gluten: found in products made from wheat, barley and rye. Although new research indicates gluten is not the issue unless you have celiac disease.
- Soy: found in products made from soy beans.
There are also a number of artificial additives known to trigger symptoms:
- Colours: added to a wide variety of foods such as lollies, cakes, sauces and many more to change or improve the colour of the product
- Preservatives: added to extend the shelf-life of products
- Antioxidants: also added to preserve particular products and extend their shelf-life
- Flavour enhancers: added to enhance the flavour of bland foods.
Elimination Diets For Diagnosing and Treating Food Intolerance
Food intolerance does not involve the immune system, nor is there any evidence of actual disease.
This means that when medical investigations are completed by doctors, test results come back as negative.
Thus, the only way to diagnose food intolerance is through structured medical elimination diets.
These elimination diets have three phases:
- Elimination: suspected trigger substances are temporarily removed from the diet
- Re-Introduction/Re-Challenge: individual trigger substances are systematically re-introduced/re-challenged one at a time to identify which substance is responsible for triggering symptoms and in what amount
- Personalise: tolerated substances are re-introduced into the diet and trigger substances are avoided.
The most common elimination diet used is the low FODMAP diet.
However those who do not find success with this diet may do better on the FAILSAFE diet / RPAH Elimination diet for food chemical intolerance.
More Information on Food Intolerance and Sensitivity
11 Warning Signs You Have A Sneaky Food Intolerance
Food Chemicals and the FAILSAFE Diet (RPAH Diet): The Beginner’s Guide
Salicylate Intolerance: The Complete Guide + List of Foods
Histamine Intolerance: Everything You Need To Know Explained in Plain English
Fructose Malabsorption: A Beginner’s Guide to Treatment
Digestive Enzyme Supplements: Splitting Fact From Fiction
Lactose Intolerance: What You Need to Know to Live a Normal Life
6 Signs and Symptoms of Gluten Intolerance
All articles about Food Intolerance and Sensitivity
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This is one of the most common questions we get at Diet vs. Disease, and if you’re tired of spending all your free time trying to figure out digestive relief on your own, this article is exactly what you need.
We’re going to cover everything you need to start a low FODMAP diet successfully, so you can get through it as smoothly as possible, find relief from symptoms, and one day eat with freedom like a normal person again.
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In this article, we’re not just talking about food triggers. We’re going deeper. You’ll learn how stress, hormone shifts, and even well-meaning advice can leave people stuck with worsening IBS symptoms that no diet alone can fix.
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The FAILSAFE diet is an elimination diet to test for food chemical sensitivities.
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