Diverse weaning foods and diet patterns at multiple time points during infancy period and their association with neurodevelopmental outcomes in 6-year-old children

Background/Objectives: Early-life nutrition may influence neurodevelopment. This study investigated associations between dietary patterns at multiple infancy/early childhood time points and neurodevelopmental outcomes at age 6. Subjects/Methods: An administrative observational cohort was constructed by merging South Korea’s National Health Insurance Service database with the National Health Screening Program for Infants and Children (NHSPIC). Parent-reported diet data were collected from 4–6 months through 30–36 months; dietary pattern clusters were derived using polytomous latent class analysis (poLCA). Neurodevelopment at 66–72 months was assessed using the Korean Developmental Screening Test (K-DST). Results: Among 133,243 eligible children, four dietary clusters were identified. The control cluster (53.4%) was characterized by breast milk feeding, timely weaning (4–6 months), diverse foods, and appropriate meal/milk patterns; Cluster 1 (36.0%) showed selective/picky ingredient intake at 1 year; Cluster 2 (6.6%) had low human milk prevalence, late weaning, diverse ingredients but higher juice intake and fewer meals; Cluster 3 (4.0%) had late weaning, low dietary diversity, and formula feeding. Compared with control, adjusted odds ratios (aORs) for unfavorable total K-DST outcome were 1.209 (95% CI, 1.156–1.266) for Cluster 1, 1.418 (1.312–1.532) for Cluster 2, and 1.741 (1.593–1.903) for Cluster 3, consistent across all domains. Conclusions: Dietary patterns in infancy and early childhood are associated with neurodevelopmental outcomes at age 6.