What is the Difference Between Allergy and Intolerance?

The main difference between an allergy and an intolerance lies in the involvement of the immune system. Here are the key differences between the two:

1. Immune system involvement: Allergy involves an immune system response, where the body identifies a usually harmless substance as a threat and produces antibodies called Immunoglobulin E (IgE), leading to an allergic reaction. In contrast, food intolerance does not involve the immune system and is a chemical reaction that some people have after consuming certain foods.
2. Symptoms: Symptoms of food intolerance typically affect the digestive system and can include nausea, gas, cramps, belly pain, diarrhea, irritability, or headaches. Food allergies can cause various symptoms, some of which can be life-threatening, such as hives, vomiting, belly pain, throat tightness, hoarseness, coughing, breathing problems, or a drop in blood pressure.
3. Severity: Food intolerance reactions are generally less severe than food allergies and do not cause anaphylaxis, a life-threatening condition. Food allergies can lead to life-threatening reactions, even if previous reactions have been mild.
4. Causes: Food intolerances can occur due to enzyme deficiencies, sensitivity to food additives, or reactions to naturally occurring chemicals in foods. Food allergies are caused by the immune system overreacting to a specific food protein, leading to the production of IgE antibodies that trigger an allergic reaction.

In summary, food allergies involve the immune system and can cause severe, life-threatening reactions, while food intolerances are chemical reactions that typically affect the digestive system and are less severe.

Comparative Table: Allergy vs Intolerance

Here is a table comparing the differences between allergy and intolerance:

In summary, the main difference between an allergy and an intolerance is that an allergy involves an immune system response, while an intolerance does not. Allergies can cause more severe symptoms and may even be life-threatening, whereas intolerances typically cause less severe, digestive-related symptoms.