Gender differences in the mediation of BMI and hepatic steatosis by sex hormones: Insights from NHANES 2017 to 2023

Obesity, often assessed by body mass index (BMI), is closely associated with hepatic steatosis, but the role of sex hormones in mediating this relationship, particularly between genders, is not fully understood. Using National Health and Nutrition Examination Survey data from 2017 to 2023, we investigated gender differences in how sex hormones mediate the relationship between BMI and hepatic steatosis. A total of 9383 participants were included, with controlled attenuation parameter (CAP) used to assess liver fat accumulation. Nine sex hormones were measured, and relevant covariates were adjusted for, employing weighted multivariate linear regression to identify the mediators between BMI and hepatic steatosis. BMI was positively correlated with hepatic steatosis in both men and women. Mediation analysis showed that sex hormones mediated the relationship between BMI and hepatic steatosis. In males, hormones such as 17α-hydroxyprogesterone (2.18%), estrone sulfate (0.88%), estrone (0.43%), follicle-stimulating hormone (FSH) (0.08%), and sex hormone-binding globulin (SHBG) (6.95%) played a role. In females, 17α-hydroxyprogesterone (0.25%), progesterone (0.39%), FSH (0.53%), luteinizing hormone (0.31%), and SHBG (8.15%) mediated the association. Our study reveals that sex hormones play a key role in mediating the relationship between BMI and hepatic steatosis in a gender-specific manner.