Infant feeding practices and physician diagnosed atopic dermatitis: a prospective cohort study in Taiwan.

It is common to recommend breastfeeding and a delayed introduction of solids to prevent atopic dermatitis (AD). However, the scientific evidence for this is inconclusive. The aim of this study was to explore the effect of breastfeeding and solids on AD, when taking account of reverse causality. This on-going birth cohort study was designed to sample 24,200 representative post-partum women and their babies from the Taiwan National Birth Registration database. Using two home interviews at 6 and 18 months after birth, with structured questionnaires about diet and physician's diagnosis of AD by parental reports, a total of 20,172 pairs (83.4%) were reviewed completely. Considering reverse causality, we excluded 2399 children with AD in the first 6 months of life and 18,733 were finally recruited. All study participants provided informed consent as approved by the Ethics Review Board of the National Taiwan College of Public Health. After adjustment for potential confounders, the overall results showed that the increased duration of breastfeeding seemed to increase the risk of AD at 18 months in children. However, no significant effect was found for the delayed introduction of solids on the risk of AD. There is no evidence of a protective effect of prolonged breastfeeding and a delayed introduction of solids against AD among children at age 18 months, and may even be a risk factor of AD.