Formula and breast feeding in infant food allergy: A population-based study

Aim To determine whether infant-feeding practices, including duration of exclusive breastfeeding and use of partially hydrolysed formula, modify the risk of developing infant food allergy. Methods In an observational population-based study, 1 year olds were recruited from community immunisation clinics in Melbourne, Australia. Parent-reported data on infant-feeding practices and potential confounders were collected prior to infant skin prick testing for four food allergens. Sensitised infants attended hospital-based oral food challenges to establish food allergy status. Multiple logistic regression was used to investigate associations between breastfeeding and formula-feeding and infant food allergy adjusting for possible confounding variables. Results A total of 5276 (74% response) infants participated. Of the 4537 for whom food allergy status was determined, 515 (11.3%) were food allergic (challenge-proven in the context of skin prick testing positive (≥2 mm)). After adjusting for confounding variables, there was no association between duration of exclusive breastfeeding and food allergy. Use of partially hydrolysed formula did not reduce the risk of food allergy compared with cow's milk formula in the general population (adjusted odds ratios 1.03 (confidence interval 0.67-1.50)). Conclusion Duration of exclusive breastfeeding and use of partially hydrolysed formula were not associated with food allergy at 1 year of age in this large population-based study. These findings have implications for population-based infant-feeding guidelines and do not support the use of partially hydrolysed formula for food allergy prevention.