Contribution of health literacy and sociodemographic factors to body mass index among Croatian adults

Abstract

Introduction: Obesity is a chronic disease with serious health consequences, including cardiovascular diseases, diabetes, and certain cancers. Identifying factors associated with BMI is essential for prevention and public health planning. This study aimed to examine the contribution of health literacy and sociodemographic factors to BMI among adults in Croatia. Methods: A cross-sectional study was conducted among 195 adults residing in Croatia. Data were collected in person using paper-based instruments. Participants independently completed the sociodemographic and lifestyle section, whereas the SAHLCA-50 was administered face-to-face by a member of the research team. Spearman's rank correlation and multiple linear regression analyses were used to examine associations with BMI and identify its independent predictors. Results: The median BMI was 25.1 (IQR 22.4–28.6), with 34.9% of participants overweight and 17.4% obese. Significant correlations were observed between BMI and age (ρ = 0.372, P < 0.001), sex (ρ = -0.176, P = 0.014), education (ρ = -0.193, P = 0.007), and health literacy (ρ = -0.172, P = 0.016). Regression analysis showed that only age and sex were significant predictors of BMI, explaining 13.1% of the variance (adjusted R² = 0.131). Health literacy and the remaining sociodemographic variables were not significant predictors of BMI in the multivariable model. Conclusions: Age and sex were independently associated with BMI, whereas health literacy was not a significant predictor after adjustment for sociodemographic characteristics. Further studies incorporating detailed behavioral, lifestyle, and socioeconomic variables are needed to clarify the relationship between health literacy and BMI.