Mediating Effects of Lipid Biomarkers and Sex‐Specific Moderation on the Associations Between Anthropometric and Dietary Factors With Insulin Resistance

INTRODUCTION: Various anthropometric and dietary indicators influence insulin resistance (IR), and lipid biomarkers may play a pivotal mediating role in these relationships. To investigate the mediating effects of lipid biomarkers on the relationships between anthropometric, dietary indicators, and IR, and the moderating role of sex in these associations. METHODS: A hospital-based cross-sectional study was conducted with 169 participants. Parallel mediation models assessed the mediating effects of lipid biomarkers (triglycerides, HDL, LDL, and total cholesterol) on the relationships between anthropometric (BMI, waist circumference, waist-to-hip ratio, and waist-to-height ratio) and dietary indicators (at least one starchy staple, at least one fruit, consumed all five recommended food groups (ALL-5), global dietary recommendations (GDR) score, and noncommunicable disease risk/protect scores) and IR. Moderated mediation analyses evaluated the moderating effect of sex. Statistical analyses were bootstrapped. RESULTS: The cumulative effect of lipid biomarkers fully mediated the relationship between WHtR and IR (Indirect Coef. = 0.65; 95% CI [0.02, 1.70]). TG significantly mediated the associations between WHR and IR (indirect Coef. = 0.55; 95% CI [0.11, 2.63]), BMI and IR (indirect Coef. = 0.76; 95% CI [0.17, 2.27]), and WC and IR (indirect Coef. = 0.72; 95% CI [0.04, 2.63]). Furthermore, LDL-C (Indirect Coef. = 1.99; 95% CI [0.24, 9.61]) and HDL-C (Indirect Coef. = 0.55; 95% CI [0.03, 2.57]) mediated the relationships of starchy staple and fruit intake with IR, respectively. Sex moderated the direct effect of WC on IR (interaction Coef. = 5.11, p = 0.002) but did not moderate the indirect pathways involving lipid biomarkers. CONCLUSIONS: These findings elucidate the intricate interplay between body composition, diet, lipid biomarkers, sex, and IR, providing insights for developing targeted prevention and intervention strategies to combat IR.