What is the difference between a food allergy and an intolerance or sensitivity?
A true food allergy is an immediate immune reaction to a food causing swelling, itchiness or airway constriction, known as an anaphylactic reaction. A food sensitivity or intolerance is a loosely used term to describe a reaction by a different part of the immune system that does not cause any overt symptoms. This is a delayed type immune reaction and symptoms may take up to 72 hrs. A food intolerance may also be due to the lack of a particular enzyme such as Lactase which is needed to breakdown the milk sugar lactose.
