Food Sensitivities- Allergy vs Intolerance

A blog post by Cat Moore

Nowadays it’s common to hear someone say they are allergic to this or intolerant to that, but what really is the difference between being intolerant and being allergic to a food?

Food Allergy

A food allergy elicits an immune response from the body. Our body produces things called antibodies that bind to things like viruses, bacteria, and allergens. They tell our body there is a foreign invader and kick starts the immune system to attack. In the case of a food allergy, a specific antibody, immunoglobulin E (IgE) is produced in response to a specific food molecule, like peanuts, shellfish, wheat, soy, or dairy. These response result in various symptoms including some as serious as anaphylaxis which is life threatening. Allergic reactions usually occur in areas like the GI tract and the air and nasal passageways. This is why a common symptom of a severe allergic reaction is for the throat or nose to swell.


Food Intolerance

On the other hand, most people commonly mistake an allergy with an intolerance. While an allergy elicits an immune response, intolerance is localized in the GI tract and the response comes specifically from that. Intolerance stems from a lack of an enzyme needed to break down a certain food. Intolerances usually have a slower onset than an allergic reaction, with some common symptoms being bloating, upset stomach, diarrhea, nausea, or vomiting.  Though in most cases symptoms of intolerance are milder than an allergic reaction, in some cases intolerance symptoms can be quite severe. Finally, in order to have a reaction to a food you are intolerant to, you would need to eat a significant amount of the food. For people who are highly allergic to a certain food, even the smallest bit may lead to severe symptoms. **

** When it comes to figuring out whether you have an allergy or intolerance, it is best to consult your doctor.