Food intolerance is a catch-all phrase to describe adverse reactions to foods that are not immunologically mediated. Intolerances are just that – development of symptoms after eating foods that someone may poorly tolerate.
Intolerances can result from metabolic properties of the food (e.g., a person’s inability to digest lactase in milk, resulting in diarrhea and lactose intolerance), pharmacologic (e.g., increased heart rate from caffeine, flushing from alcohol), Scombroid poisoning (food poisoning from ingesting improperly stored fish, which can release histamine and mimic an allergic reaction) or without a known mechanism (asthma and respiratory symptoms from sulfites).
