Ultra-processed food intake during pregnancy and its association with early brain and behavioral development in children: a prospective cohort study

Growing evidence suggests that maternal consumption of ultra-processed foods (UPFs) during pregnancy may adversely affect offspring neurodevelopment. However, the underlying neurobiological mechanisms remain poorly understood. This study combines a comprehensive review of the current literature on maternal UPF consumption during pregnancy, brain development, and behavioral outcomes with empirical evidence from a prospective birth cohort. Specifically, we examined whether neonatal white matter (WM) microstructure may represent a pathway linking maternal UPF consumption with early behavioral development. Data were analyzed from three subsamples of mother-child pairs participating in the Barcelona Life Study Cohort (BiSC; 2018-2021): 560 pairs with maternal dietary and 18-month behavioral data, 43 with maternal dietary and neonatal WM tractography data, and 32 with complete dietary, neuroimaging, and behavioral assessments. Maternal UPF consumption was assessed during the second trimester using food-frequency questionnaires. Neonatal WM microstructure was examined at one month of age using diffusion tensor imaging and deterministic tractography. Behavioral outcomes at 18 months were assessed using the Child Behavior Checklist for Ages 1½-5 (CBCL 1½-5) and the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R). Associations among UPF exposure, WM measures, and behavioral outcomes were analyzed using regression models with permutation testing and hierarchical regression analyses to assess potential mediation. Higher maternal UPFs consumption, was associated with greater behavioural dysregulation at 18 months, including oppositional-defiant, attention, withdrawn, aggressive, and attention-deficit/hyperactivity disorder (ADHD)-related problems. Maternal UPF consumption was associated with variations in WM microstructure in the superior longitudinal fasciculus, cingulum bundle and forceps minor. These variations were further associated with less favorable behavioral outcomes. Diffusivity measures in the right superior longitudinal fasciculus attenuated the association between maternal UPF consumption and oppositional-defiant problems. Findings from both the literature review and cohort analyses support an association between maternal UPF consumption and early behavioral outcomes. Neonatal WM microstructure may represent a potential neurobiological pathway linking maternal dietary habits and early behavioral development.