The explanation of educational disparities in adiposity by lifestyle, socioeconomic and mental health mediators: a multiple mediation model

Background: Numerous studies report an inverse association between education and obesity. This study assesses potential mediators of educational disparities in adiposity, hypothesizing mediating roles for lifestyle, socioeconomic, and mental health factors. Methods: A cross-sectional, population-based sample from Czechia included 2,154 adults aged 25–64 years (54.6% women). Education was classified as high, middle, or low. Adiposity was modeled as a latent variable from body fat percentage, BMI, waist circumference, and visceral fat. Potential mediators included unhealthy dietary behavior, alcohol intake, smoking, sedentary behavior, income, stress, depression, and quality of life. Age-adjusted, sex-specific multiple mediation models were estimated. Results: Education showed a negative direct effect on adiposity in both sexes. For men, an indirect effect operated via sedentary behavior (β = 0.041; 95% CI [0.025–0.062]) with a mediation ratio of 23.7%. In women, indirect effects operated via dietary risk (β = −0.023; 95% CI [−0.037, −0.013]), alcohol intake (β = −0.006; 95% CI [−0.014, −0.001]), sedentary behavior (β = 0.012; 95% CI [0.004, 0.023]), income (β = −0.022; 95% CI [−0.041, −0.004]), and mental health (β = −0.007; 95% CI [−0.019, −0.001]). Total mediation ratio in women was 30.5%. Conclusions: Sedentary behavior mediated the education–adiposity association in both sexes, more strongly in men. In women, unhealthy diet and lower income also partially mediated the educational gradient in adiposity.