How common is it?

According to Allergy New Zealand, as many as 10 Kiwi babies are born every day who will go on to develop a food allergy. Overseas studies indicate an increase in prevalence and more young children in New Zealand are being referred to clinics for diagnosis, monitoring and support.  

Allergy has tended to be a developed-country problem. The reasons for this are complex, but some experts believe our immune systems don't have enough to do in the hygienic environments we've created ... and if the developing immune system doesn't have sufficient diseases to fight, it starts a scrap with the first allergens it most frequently comes into contact with. In babies, that could be allergens in breast milk, infant formula, or first solids.

Immunologists (allergy specialists) estimate between 6 and 8 percent of children have food allergies, and that 2 to 4 percent of adults do. Fortunately, most children will outgrow their allergy. But allergies to peanuts, fish, and shellfish tend to be lifelong.

Kids and additives and colourings

Many people believe their children have an allergy to artificial food colourings and additives. But these reactions aren't allergies. They're allergy-like intolerances or additive intolerances (see Allergy or intolerance?).

There's also a lot of debate about food colourings causing hyperactivity in children. It's hard to give a definitive answer because the many studies examining the links are difficult to assess. But an Australian expert committee concluded that "well-designed studies have failed to show a consistent relationship between a range of behavioural problems in children and the consumption of food additives".