When someone with a food allergy ingests the food they are allergic to, their immune system mistakenly identifies it as harmful and the resulting immune response results in the various symptoms.
Food allergy affects 10% of children up to one year of age, 8% of children up to five years of age, and approximately 2% of adults. Prevalence of food allergy has increased in Australia over the last 10-years.
Most of the time there is no parental history of food allergy in affected children. Siblings of children with food allergy are more likely to have food allergy themselves however.
Food allergy affects 10% of children up to one year of age, 8% of children up to five years of age, and approximately 2% of adults. Prevalence of food allergy has increased in Australia over the last 10-years.
Most of the time there is no parental history of food allergy in affected children. Siblings of children with food allergy are more likely to have food allergy themselves however.
Broadly speaking, allergic reactions to foods fall into 2 categories; IgE-mediated and non-IgE-mediated.
Symptoms of food allergies can vary from person to person and can range from mild to severe. Common symptoms of IgE-mediated food allergy include:
Several foods are known to cause allergic reactions more frequently than others. Nine out of ten cases of food allergy are triggered by the following foods:
Diagnosis typically involves a combination of medical history, physical examination, and allergy testing, such as skin prick tests or blood tests.
It is important to differentiate food allergy from adverse reactions to foods. Food poisoning, food aversion, and local skin irritation from food contact are just some examples of adverse reactions to foods that are not an allergy.
False positive skin prick testing or specific IgE testing to foods is not uncommon, especially in people with eczema. Not everybody who has a positive skin prick or blood test to a food has an allergic reaction to that food on ingestion.
In addition, false negative skin prick testing can occur to some foods.
Supervised oral challenges, as the gold standard diagnostic test for food allergy, may be required in some individuals.
