Differential longitudinal effects of frequent sweetened food consumption at different exposure ages on child cognitive, language, and motor development

Background: Evidence reveals frequent sugar consumption worsens cognition in animal models, and similar effects on child development are probable. We aimed to investigate the influence of sweetened foods (SFs) on child developmental trajectories. Methods: The prospective cohort recruited 3-month-old children in Taiwan from 1st April 2016 to 30th June 2017. Developmental inventories including cognitive, language, and motor domains, were measured at the age of 3-,12-, 24-, and 36 months old via in-person interviews. We constructed latent growth models with covariates to estimate the influence of SFs on child development. Results: Ultimately, 4782 children (50.7% boys) were included in the statistical analysis. In the cognitive domain, consumption at one year of age significantly affected the intercept, but not the linear slope and quadratic term (intercept: estimate = −0.054, p < .001); consumption at two years of age significantly affected the intercept and quadratic term (intercept: estimate = −0.08, p < .001; quadratic term: estimate = −0.093, p = .026), but not the linear slope. In the language domain, only consumption at two years of age significantly affected the intercept (estimate = −0.054, p < .001). In the motor domain, consumption at two years of age significantly affected the linear slope and quadratic term (estimate = 0.080, p = .011 and estimate = −0.082, p = .048, respectively). Conclusion: We found SFs exposure at different times has different negative effects on child development. Early exposure to SFs harmed children's cognitive function. Relatively late exposure to SFs not only deteriorated children's cognitive and language abilities but also decelerated developmental velocity in cognitive and motor domains.