Introduction - Allergenicity

There are a variety of adverse reactions that some consumers experience following exposure to certain foods. Adverse reactions to food can include immunological reactions, such as IgE-mediated and non-IgE-cell-mediated responses (14). There are also non-immunological reactions such as food intolerances, and allergy-like intoxications (14). The non-immunologic reactions are often confused with true food allergies because similar symptoms are observed.

True Food Allergies - Immunological Reactions

A true food allergy is an abnormal reaction that involves the response of the body’s immune system to a certain component in a food or ingredient, usually a protein (1, 4).

The immune responses of a true food allergy can be separated into two categories, IgE-mediated and non-IgE-cell-mediated (1, 2). The more common allergic response, IgE-mediated, also referred to as an immediate hypersensitivity reaction, involves the rapid onset of symptoms, and is mediated by immunoglobulin E (IgE) antibodies. The IgE-mediated response will be discussed in more depth, further along in the lesson.

A non-IgE-cell-mediated response, also referred to as a delayed hypersensitivity reaction, involves the delayed onset of symptoms, usually 24 hours or longer after exposure or ingestion of the food (4).