Food intolerance is more common than food allergy. The medical definition of food intolerance is wrapped around lactose and gluten. Lactose intolerance and gluten intolerance are usually inherited but can be acquired and they involve a deficiency in the enzymes needed to breakdown these foods.
Food intolerance reactions is an adverse food-induced reaction that does not involve the immune system which, depending on their causality, are divided into the following types of intolerances:
*Enzymatic
*Pharmacological, i.e. reactions caused by either naturally derived or added chemicals that reduce a pharmacological effect in the individual
*Idiosyncratic reactions with undefined food tolerance
Though symptoms of food allergy or intolerance may be very similar, the latter do not involve the immune system and are typically triggered by molecules that are considerably smaller than proteins. The triggers are substances that are naturally present in foods, arose for processing methods, or are added during processing.
Food intolerances probably make up the majority of adverse reactions. Examples of food intolerances include:
*Reactions from toxic contaminants – histamine in scombroid fish poisoning, toxins secreted by Salmonella or Shigella
*Pharmacologic reactions e.g. to caffeine in coffee, tyramine in aged cheeses
*Idiosyncratic and psychological reactions – e.g. sulfite induced asthma
The best example of food intolerances are lactose intolerance and sulfite induced asthma. It is a disorder in which a deficiency of B-galactosidase in the small intestine results in reduced ability to digest and absorb lactose.
These illnesses are of lesser importance than allergy because of finite tolerance levels for the offending foods among affected individuals.
Although symptoms can be severe and very distressing, they are not potentially fatal.
The reaction of food intolerance