ALLERGY VS INTOLERANCE

Allergy, hypersensitivity, intolerance...

The specific terms food allergy, hypersensitivity and intolerance are all commonly used interchangeably, with some evident confusion regarding the actual difference between them. 

Essentially these terms all relate to an adverse physiological response to a particular food; however the mechanisms by which this occurs are very specific to the individual type of food sensitivity in question. These reactions can be categorised as either immunological (IgE or IgG mediated) or non-immunological in nature and can initiate an immediate (minutes to hours) or delayed (several hours to days) response to a particular food. Identifying the specific reactive mechanism triggered by the ingestion of this food is vital to understanding the management and implementation of appropriate dietary interventions to limit potentially unpleasant (and in some cases, life threatening) symptoms.


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IgE food allergy

A classic IgE allergy occurs when the immune system produces this type of antibody that mediate the release of histamine and other reactive substances, leading to an immediate allergic reaction...
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IgG food intolerance

While IgE antibodies are responsible for acute allergic reactions, gig-mediated manifestations take much longer to develop. IgG antibodies play a significant role in the shaping of the bodies normal immune system.
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Food intolerance

Non immunological food intolerance is generally caused by a genetically-inherited defect in an individuals ability to metabolise a food component due to enzyme deficiencies.