Childhood food allergies are definitely on the rise. Terms such as ‘nut-free’, ‘egg-free’, ‘Epipen’, ‘anaphylaxis plan’ are all too common. The Wiggles even have a song all about allergies! On a serious note, the number of children presenting to hospital in Australia with food-related allergic reactions has steadily increased in the past decade. Every now and then a media report of a child who has died from an anaphylactic food-related reaction, usually while at school, will remind us of the imminent risk to our children. It’s enough to make any parent feel uncomfortable.
Allergic reactions to food range from mild to severe, with the most severe form being difficult breathing leading to loss of consciousness (anaphylaxis). Most food allergies will be evident in the first 5 years of a child’s life, though it is possible now to identify babies who are going to be at higher risk of food allergies even before they commence solids. Allergic reactions take place when the body responds adversely to proteins found in food. The most common food allergies are to cow’s milk, eggs and peanuts – all of which contain their own unique proteins. While we are not sure why food allergies are on the rise, there are several proposed explanations. The hygiene hypothesis seems to have caught on well (essentially that living a clean lifestyle leads to less exposure to dirt and infections which then sets up a child to develop food allergies). But we also know that children in Western culture tend to have delayed introduction of solids in their diet, which also increases their risk of food allergies in later life.
The mechanisms of food allergies are complex as are the presentations and management. If you do suspect that your child may have a food allergy, it is best to discuss your concerns with your GP who will likely refer you to an allergy specialist. If appropriate, skin prick testing will most likely take place. It is important to note that positive skin prick testing (ie. a large reaction on the skin) does not necessarily directly correlate to a food allergy. The test must be interpreted on the background of what the child can safely eat or if necessary after observation of a food challenge test. A food challenge test is an medical observation of the child eating gradually larger amounts of a particular food type, (for example, boiled egg or peanut butter). Note is made of any reactions and whether or not the child would be safe to continue eating this food type. This type of test is useful to clarify whether the child actually has a food allergy or if they have indeed grown out of one. Yes, the good news is that most children will out grow their food allergies (especially those to cow’s milk, soy, wheat or egg). In terms of prevention of food allergies, one of the best things a parent can do for their child is the early introduction of solids from 4-6 months, which includes (where possible) the introduction of eggs, nuts and other potential allergens.