The Impact of Maternal Dietary Avoidance During Breastfeeding on Physical Growth and Social–Emotional Development in Infants with Food Allergies: A Prospective Cohort Study

Background: Maternal dietary avoidance during breastfeeding of infants with food allergies (FA) is common, but its impact on growth and development is unclear. Methods: This prospective cohort study enrolled infants aged 4–6 months who were mainly breastfed from the child health care clinic of Children’s Hospital of Chongqing Medical University, Chongqing, China. The participants were classified into a group with clinically diagnosed FA and a non-food allergies (NFA) group. To analyze avoidance extent, the FA group was stratified into high (≥5 types) and low (<5 types) avoidance subgroups based on the median number of avoided food categories. Outcomes included anthropometric Z-scores and ASQ:SE-2 social–emotional scores at 12 months, analyzed using Generalized Estimating Equations. Results: High avoidance mothers comprised 50% of the FA group. Compared to the high avoidance group, the non-FA group showed significantly better linear growth (β = 0.84, 95% CI 0.38–1.30, p < 0.001). Weight and head circumference showed no differences. High avoidance was associated with higher ASQ:SE-2 scores versus both the low avoidance and non-FA groups (p < 0.001), indicating greater social–emotional concerns. Conclusions: Extensive maternal dietary avoidance was associated with suboptimal linear growth and higher social–emotional risk scores in infants with FA, underscoring the need for integrated nutritional and developmental monitoring. These findings warrant cautious interpretation given the exploratory nature of this single-center study.