Gender Differences in Weight Loss Extent Following Bariatric Surgery.

Background/Objectives: Metabolic-bariatric surgery (MBS) is a highly effective treatment for severe obesity; however, gender disparities exist in access and postoperative outcomes. Despite men presenting with higher baseline weight and comorbidity burden, they are significantly underrepresented among MBS patients. Existing evidence on gender-specific outcomes remains inconclusive, particularly within Mediterranean populations under updated clinical guidelines. To evaluate gender differences in weight loss outcomes following sleeve gastrectomy in an Italian cohort managed under current multidisciplinary protocols. Methods: A prospective observational study was conducted and a total of 131 patients (109 females, 22 males) underwent sleeve gastrectomy at a single center. Anthropometric and metabolic parameters were assessed at baseline and 12 months postoperatively. Outcomes included absolute weight loss (TWL%), percentage of initial and excess body weight lost (EWL%), and waist circumference. Group comparisons used t-tests (with Welch's correction if variances were unequal) and regression models adjusted for baseline BMI and age. Results: At 12 months, men achieved significantly greater absolute weight loss than women (-36.6 kg vs. -31.2 kg; p = 0.028), although no significant differences were observed for TWL%, EWL%, or waist circumference reduction. Gender remained a significant predictor of absolute weight loss in multivariate analysis, but not of proportional weight loss. Both genders showed similar rates of achieving clinically significant weight loss thresholds. Conclusions: While men exhibited greater absolute weight loss, relative weight loss outcomes were comparable between sexes. Gender disparity is observed in the utilization of MBS. These findings highlight the importance of equitable surgical access and tailored postoperative care.