Obesity poses a significant challenge to societies and healthcare systems worldwide. Metabolic bariatric surgery (MBS) has emerged as a proven primary intervention for severe obesity. This cross-sectional study investigated the interplay between sociodemographic and psychological factors and their influence on attitudes toward eating and body mass index (BMI) among candidates undergoing MBS. Recruitment took place over a period of more than five years. Sociodemographic and BMI data were collected, and psychological evaluations were conducted using standardized self-report questionnaires and clinical interviews. Data were analysed using Pearson and Spearman correlations, multiple linear regression, and bootstrapped mediation analysis. After exclusion of those who did not meet surgical suitability criteria, declined participation, or had incomplete data, the study included 515 participants. Significant associations were found between lower educational attainment, unmarried status, and higher BMI. High neuroticism was linked to increased BMI, depression, and anxiety. Resilience was moderately negatively correlated with anxiety and depressive symptoms and showed a small but statistically significant indirect (partial mediating) effect on the relationship between neuroticism and anxiety or depressive symptoms, although its small magnitude and the cross-sectional design preclude causal interpretation. The findings demonstrate that several variables play substantial roles in eating attitudes and influence BMI in this population. Notably, resilience emerges as a significant psychological factor. However, further research is warranted to fully elucidate its role and impact. These insights provide valuable guidance for refining preoperative assessments.