How often do you go to a child’s birthday party or a play date and find a list a mile long of all the different food allergies being catered for?
According to the Australasian Society of Clinical Immunology and Allergy, “food allergy affects 10% of children up to 1 year of age [and] between 4-8% of children aged up to 5 years of age”. In Australia, hospital admissions for anaphylaxis due to food allergy in children aged 0 to 4 have increased fivefold in the last decade. It’s no wonder ‘everything-free’ parties are now the norm.
But are we seeing an increase in food allergies or intolerances, and what differentiates the two?
Food Allergy Or Intolerance?
The key factors differentiating a food intolerance from a food allergy are:
- severity and complexity of symptoms; and
- whether or not the immune system is involved
Someone suffering from a food intolerance may experience non-life-threatening symptoms such as gastric upset (e.g. stomach pain, bloating, constipation. diarrhoea) and skin rashes. This is due to a chemical reaction and the symptoms are generally limited to the digestive system. Food intolerance sufferers may also be able to eat small amounts of the offending food without serious repercussions. A vast number of foods can cause these symptoms including nuts, dairy, wheat, sugar, salicylates, preservatives and additives.
A food allergy on the other hand causes an immune reaction with the very real risk of anaphylaxis. Symptoms of food allergy include swelling of the lips, face and eyes, wheezing, tightness in the throat, dizziness and difficulty breathing. The most common food allergies include tree nuts, peanuts, cow’s milk, egg, sesame, soy, fish, shellfish and wheat. According to the Australaisian Society of Clinical Immunology and Allergy, these foods make up 90% of all food allergic reactions.
How Are Food Allergies And Intolerances Diagnosed?
There are a number of different tests that can be used to diagnose a food allergy or intolerance. These tests vary in accuracy and invasiveness. Whilst these tests alone do not always provide clear-cut answers, they are usually combined with a child’s family and personal history of symptoms and a physical examination to provide a diagnosis.
Many orthodox and complementary practitioners will recommend keeping a food journal to identify a direct link between a particular food being consumed and symptoms being presented. Once one or two suspect foods have been identified, a child may be placed on an elimination diet. By eliminating the suspect foods for a week or two and then re-introducing them into the diet, it may be possible to pinpoint the foods causing the most problems. After avoiding the suspect foods for a few months, the offending foods can be gradually reintroduced into the diet to determine whether the intolerance or allergy has cleared on its own.
Skin Prick Testing
A skin prick test involves placing a drop of solution containing the suspect food on the back of the forearm or back. The skin is then pricked with a needle to allow small amounts of the substance to enter below the skin surface. A positive result will present, usually within 30 minutes, as a raised, red swelling (called a wheal).
Unfortunately however positive results are not always accurate. According to Food Allergy Research & Education (FARE) “about 50-60 percent of all skin prick tests yield “false positive” results, meaning that the test shows positive even though [the patient is] not really allergic to the food being tested.”
Skin prick tests are generally not recommended for children under 12 months. This is due to increased risk and greater complexity of interpretation of results.
Blood Tests For Allergen Specific IgE
Blood tests may be used to measure a child’s immune response to particular foods (by checking the amount of immunoglobulin E (IgE) antibodies in the bloodstream). These tests are often performed when:
- skin testing is not easily available
- when skin conditions such as severe eczema preclude skin prick testing, or
- when a person is taking medications (such as antihistamines) that interfere with accurate skin prick testing.
If you would like some more information on allergies relating to your child, please email me to discuss a private 1:1 paediatric nutrition consultation.
*This article was first published by Katie Harding @ Nourished Beginnings on www.mumlifeaustralia.com