Background: Previous research on health inequalities has demonstrated a strong association between educational attainment and poorer health status, however, only few studies have examined the possible contribution of health literacy (HL) in explaining this relationship. This study, therefore, aims to study whether HL could be a pathway by which educational attainment affects health status in an adult German population.
Methods: HL was assessed with the short version of the European Health Literacy Survey (HLS-EU-Q16) in the baseline examination of the German National Cohort (GNC) of the study center in Halle (Saale). Using structural equation modeling (SEM), we modeled HL as a mediator of the relationship between educational attainment and self-reported general health as measured by the Short Form-12 while controlling for age and sex. Analysis was conducted using STATA V16.  
Results: 4,692 participants were included in the study (52.2% female; mean age 50.5±12.2). In SEM, educational attainment had both a direct (standardized β = 0.136; 95% confidence interval (CI) 0.11-0.16) and an indirect effect mediated by HL (standardized β = 0.017; 95% CI 0.01-0.02) on health status. Consequently, the effect mediated by HL explained 11% of the total effect of educational attainment. In addition, HL was directly related to health status (standardized β = 0.170; 95% CI 0.14-0.20).
Conclusions: This study showed that while HL acts as a partial mediator between educational attainment and health status, it explains only 11% of the effect associated with educational attainment. On the other hand, HL itself has a direct effect on health status, independently of educational attainment, and thus directly addressing HL can potentially improve health status. Our results do not differentiate the population strata, so further research is needed to explore these effects in more detail.