The Mediating Role of Screen-Based Sedentary Behaviors in the Association of Parental Educational Level and BMI with Preschoolers’ Ultra-Processed Food Consumption

Background/Objectives: The mediating role of the diverse range of screen-based sedentary behaviors (SBs) remains understudied, particularly at younger ages. The present study examined the direct and indirect effects of parental BMI and education on ultra-processed food (UPF) consumption among preschoolers, testing the potential mediating role of screen time. Methods: The cross-sectional study sample comprised 919 kindergarten children (484 boys, 52.7%), with ages ranging from 2.2 to 6.8 years (mean: 4.7 ± 1.0 years). Screen-based sedentary behaviors (television viewing, smartphone use, tablet use, computer use, and playing electronic games) were measured by proxy-report fulfilled by parents, separately for weekdays and weekends. UPF consumption (drinks/yogurts, packaged/fast foods, and sweet/salty snacks) was assessed via 24 h recall scales. Path analysis mediation models tested direct effects of maternal/paternal BMI and education on UPF intake, and indirect effects through screen time, controlling for child age and sex. Results: Lower parental education and higher parental BMI were associated with increased mobile device use and UPF consumption (r = 0.10–0.28). Screen-based sedentary behaviors mediated the association between maternal BMI and UPF pathways (15–90% of total effects), particularly for sweet and salty snacks (50–90%). Parental education effects were also mediated by screen time (9–23% indirect effects), with paternal education showing stronger protection against packaged/fast foods. Conclusions: Mobile devices and watching television partially mediate intergenerational transmission of obesogenic dietary patterns from parental BMI/education to preschoolers’ UPF consumption. Findings of the current study support family-centered interventions targeting screen-time limits and UPF exposure, mainly at the weekends, to prevent early obesity trajectories.