Questioning the role of egg in lactation for induction of specific tolerance: the QuEST trial.

With increasing rates of food allergy in countries such as Australia, there is a growing need to understand the role and effects of early food allergen exposure in the development of tolerance to food allergens. Egg allergy is now the most common food allergy in babies in Australia, with almost 1 in 10 babies at 1 year of age in the community now having an egg allergy. Previous recommendations to prevent food allergy through early allergen avoidance of certain foods have failed and now have instead been associated with increased risk of allergy development. With rates of food allergies increasing in our young Australian children, prevention is therefore the key to reduce allergies and the associated burden on the individual, the family and the health care system. In recent studies we have found a significant number of babies to have food allergy reactions the first time they eat a solid food (for example, egg) at 4-6 months of age. This indicates that earlier strategies may be needed in some babies to prevent food allergy. To develop tolerance (and not have a food allergy reaction) to a food it is currently thought that regular eating of that food is needed. However the ideal age to eat the food and amount of the food is unknown. Foods proteins are known to pass from the breastfeeding mother’s diet into breast milk. Current thinking is that the regular presence of food proteins in breast milk will help babies to develop tolerance and hence prevent allergies to foods. The primary aim of the study is to investigate the effect of a breastfeeding mother’s dietary egg intake on egg levels in breast milk during the first six weeks of breastfeeding. We will recruit women with singleton pregnancies who have a history of allergic disease, and ask the women to eat "high egg" (4-6 eggs per week), "low egg" (1-3 eggs per week) or "egg-free" diet during the first 6 weeks of breastfeeding. Differences in egg levels in breast milk samples will be measured. The study will not interfere in any way with breastfeeding or the mother’s or the baby’s nutrition. With expanding the research in this area, recommendations of what women should eat while breastfeeding can be more evidence based, especially with the goal to reduce the current rising problem of food allergy in Australia.