Food Allergy vs. Sensitivity: What’s the Difference?


Gluten-free, dairy-free, nut-free…specialized diets are everywhere you look. But not everyone with special dietary needs has the same reaction to their offending foods. What’s the difference between being allergic to a food and being sensitive or intolerant to it?


The key difference between a food allergy and sensitivity is the body’s response. When you have an allergy or sensitivity, your immune system gets involved. If you have an intolerance, the reaction is largely triggered in the digestive system.


Food Sensitivities
Food sensitivities and intolerances are far more common than food allergies, according to the British Allergy. Either a food triggers an intolerance in your digestive tract, where your body is unable to properly break it down, or your immune system reacts to a food you are sensitive to. For example, milk intolerance is where your body is unable to break down lactose, a sugar found in dairy products. But when you are sensitive to milk, you react to the milk protein.


Food Allergies
Your immune system is your body’s defense against invaders — whether bacteria or the common cold virus. You have a food allergy when your immune system identifies a protein in what you eat as an invader. It reacts by producing antibodies to fight it.


A food allergy or sensitivity is an immune-mediated reaction to the food. Immunoglobulin E (IgE)-mediated reaction is food allergy when that of Immunoglobulin G (IgG), it is food sensitivity. Unlike a food intolerance or sensitivity, food allergies can be fatal. In extreme cases, ingesting or even touching a small amount of the allergen can produce an intense reaction.


The Difference in Symptoms
Symptoms of food sensitivty include gas, bloating, diarrhea, constipation, cramping, and nausea. Symptoms of food allergy include hives, swelling, itching, anaphylaxis, and dizziness.