Food Allergies: Clinical Manifestations, Diagnosis, and Management

Abstract

Reactions to foods are extremely common and the etiology of these reactions determines their correct management. Adverse food reactions are not all allergic. The management of food adverse reactions ranges from complete avoidance of minute amounts of food to ingesting milk after lactase supplementation. It is, therefore, important to accurately classify reactions to foods. Adverse food reactions can be categorized into the 2 following groups: nonimmunologic and immunologic. Immunologic reactions to food are mediated by the immune system, while all other reactions fall into the nonimmunologic category. Nonimmunologic reactions are grouped into either toxic or nontoxic reactions. A toxic reaction results from the pharmacologic actions of a substance within a food. These reactions can occur in anyone who is exposed to the food and do not depend on host factors. These substances may be enzymes or any agent that could cause reactions in the body. Examples of toxic reactions include nausea from bacterial food poisoning, heavy metal poisoning, and itching and flushing from histamine ingestion as seen in scombroid fish poisoning. The consumption of foods containing caffeine, such as coffee or tea, can cause jitteriness. Tyramine in aged cheeses can cause migraine headaches and alcohol ingestion is associated