Associations of early life dietary diversity and child neurodevelopment: a prospective cohort study

BACKGROUND: Early-life nutrition is crucial for child neurodevelopment, but evidence on the role of dietary diversity remains limited, especially regarding its combined effects during pregnancy and infancy. This study aimed to investigate the independent and joint associations of maternal and infant dietary diversity score (DDS) with child neurodevelopment. METHODS: This study included 2,773 mother-infant pairs from a prospective birth cohort in Wuhan, China. Maternal DDS during pregnancy and infant DDS at 12 and 24 months of age were assessed. The Bayley Scales were used to evaluate the mental development index (MDI) and psychomotor development index (PDI) of 2-year-old children. Linear and Log-Poisson regression models were used to analyze associations, adjusting for covariates. RESULTS: Higher maternal DDS was associated with increased MDI scores (β = 0.61 per 1-point increase). Infant DDS at 12 and 24 months positively correlated with MDI (β = 0.52 and 0.34, respectively) and PDI (β = 0.28 and 0.26, respectively). Compared to the lowest tertile, the highest tertile of infant DDS was associated with significantly lower risks of cognitive development delay, with relative risk (95% confidence interval) of 0.32 (0.15-0.71) at 12 months and 0.67 (0.47-0.96) at 24 months (all P for trend < 0.05). Joint analysis showed cumulative benefits of sustained high DDS across early life stages. Specific foods, including, whole grains, red meat, vegetables, and fruits, were positively associated with neurodevelopment, while sweets showed negative associations. CONCLUSION: Greater dietary diversity during pregnancy and infancy was linked to improved child neurocognitive development, emphasizing the importance of balanced nutrition across early-life stages.