The Differences Between Type I and Type III Allergies


Immune system reactions to certain foods are widespread. Some of these are caused by a type I allergy, but many are caused by IgG-mediated food allergies. Unfortunately, it can be difficult to determine which type of reaction you are suffering, and many people need clarification.


TYPE I Food Allergy

If you have a type I allergy, even small amounts of the offending food can trigger symptoms.  These can be severe or even life-threatening. Thankfully, this is rare, affecting only around two percent of adults. When you have an allergic episode, your body’s immune system wrongly believes it is being attacked. In response, your body produces immunoglobulin E (Ig E) antibodies to fight the foreign substances. This can cause a range of immediate responses, affecting your skin (hives), stomach (vomiting), lungs (coughing and wheezing), or circulatory system (decreased blood pressure). It can also cause a systemic reaction known as anaphylaxis that can be fatal.


TYPE III Food Allergy (Delayed)

Type III food allergies, also known as food intolerances, food sensitivities, type III allergies, or delayed food allergies, can be extremely uncomfortable, but they’re not as severe as type I allergies. Type III allergies tend to be more widespread than type I allergies. They affect more people, and the symptoms can occur a few hours or several days after consuming the offending food. The good news is, while the symptoms of a type III allergy can be troubling and uncomfortable, they are not life-threatening.