Food Allergies and Intolerances

Food Allergies Intolerances are NOT the same thing. Food Allergy is an immune-mediated response to a protein.

For example: milk allergy is a response to the milk protein casein. Allergies can be very severe and even life-threatening. Food Intolerance is a hypersensitive reaction to a food chemical (natural or unnatural) or nutrient. For example: lactose intolerance is a reaction to lactose, a carbohydrate found in milk, usually because the body does not have sufficient enzyme (lactase) to breakdown lactose. Intolerances are usually less severe and can be dose dependent (e.g. a small amount of a food chemical/nutrient may be tolerated while larger amounts may not be).

Allergies can be identified using blood tests or skin prick tests (discuss with your GP), however most intolerances need to be identified using dietary investigation, with some exceptions (e.g. lactose). Food intolerances can be associated with gastro-intestinal symptoms (e.g. irritable bowel syndrome, constipation, diarrhoea, bloating, abdominal pain), skin symptoms (e.g. eczema, dermatitis), headaches, sinus, asthma and others.

There are several dietary investigation methods used to identify the cause of food intolerance and a Dietitian will conduct a full diet and symptom assessment (taking into account medical history, blood tests, family history) and prescribe the dietary method best suited to your symptoms. Different dietary investigation methods include: Simple or Strict Elimination Diets (to identify food chemicals such as salicylates, glutamates, amines); Low FODMAP diet; investigation for lactose or fructose malabsorption. You will need to keep a detailed food and symptom diary during dietary investigation.

Adelle Purbrick has a Professional Certificate in Medical Nutrition Therapy in Food Allergy and Intolerance (ASCIA and DAA), training in the Low FODMAP diet, RPAH Food Chemical Elimination Diet, SIBO, Coeliac Disease, IBD and more.