Health literacy relates to self-regulation of eating behavior through physical activity and self-efficacy pathways.

The mechanisms by which health literacy (HL), a key factor in promoting individual health behaviors, including self-regulation of eating behaviors (SREB), relates to dietary self-regulation in adults remain unclear. Specifically, further research is needed to explore the mediating roles of physical activity (PA) and General self-efficacy (GSE) between these two factors. This study aims to identify the mediating pathways through which health literacy affects dietary regulation via PA and GSE, providing a theoretical foundation for multidimensional intervention strategies. The Psychology and Behavior Investigation of Chinese Residents (PBICR-2024) included 2,366 permanent residents aged 18 years and above in Sichuan Province. The researchers used analysis of variance (ANOVA) to test for differences, Pearson's correlation coefficient to evaluate relationships between variables, and structural equation modeling (SEM) to analyze the connections among HL, PA, GSE, and SREB. Additionally, they employed the Bollen-Stine bootstrap test to assess model fit and to measure mediating effects. SEM revealed a significant direct effect of HLS on SREBQ (β = 0.075, p = 0.003), accounting for 50.48% of the total effect. Indirect effects mediated by PA and GSE accounted for 49.52% of the total effect. Specifically, GSE mediated 81.88% of the indirect effect (β = 0.061, p < 0.001), PA mediated 15.66% (β = 0.012, p = 0.002), the PA→GSE sequential pathway mediated 2.47% (β = 0.002, p = 0.012), and the model demonstrated excellent fit (χ²/df = 1.21, RMSEA = 0.01). Health literacy promotes dietary self-regulation both directly and indirectly, primarily through enhancing self-efficacy and secondarily through increasing PA (which also slightly boosts self-efficacy). Public health interventions should integrate health literacy promotion, physical activity encouragement, and psychological empowerment (targeting self-efficacy) for optimal multidimensional dietary behavior management.Registration Number: ChiCTR2400085016.Clinical trial number: ChiCTR2400085016 at 2024-05-29.