Having seen first-hand the increasing number of children with allergic reactions admitted to the RCH, Professor Katie Allen and her research group sought to identify the exact rate of food allergy in the population and devised the HealthNuts study. The study followed 5300 children from Melbourne aged 1 to 10 and assessed their reactions to specific foods known to commonly trigger allergic reactions (allergenic foods) – peanut, egg, cow’s milk and sesame. It found that over 10% of children had ‘challenge-proven allergy’, which is when a child is observed to have an allergic reaction to a specific food and treated in a safe clinical setting.