Weight loss from obesity is a global health concern associated with increased risk of chronic illness and significant healthcare costs. Sleeve gastrectomy is an increasingly popular bariatric surgery option for substantial weight reduction; however, sustained success depends on lifestyle modification. Integrating food, exercise, behavioral, and technology-based interventions into surgery can potentially enhance outcomes and promote weight maintenance. A systematic review and meta-analysis were conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) 2020 guidelines, encompassing randomized controlled trials published between 2014 and 2025. Databases like PubMed, Cochrane Library, Embase, Web of Science, and Scopus were searched. Studies included adults (age ≥18 years) with obesity undergoing sleeve gastrectomy and subjected to post-operative lifestyle interventions. The primary outcomes were weight changes, BMI, and body composition, while the secondary outcomes included comorbidities and quality of life. Risk of bias was assessed using the ROB-2 tool (www.cochrane.org). Thirty-one studies with varying follow-up durations (1-60 months) were included. The combined intervention resulted in greater weight loss (5%-30% decrease), improvement in fat mass, BMI, and cardiometabolic profiles compared to usual care. The meta-analysis revealed a high overall effect size for weight reduction, with a value of 2.56 (2.15-2.88) for the high weight reduction group and 1.88 (1.76-1.91) for the low weight reduction group. Heterogeneity among studies was moderate, with I² values ranging from 18% to 46%, indicating some variation in study populations and intervention effects. Technology-augmented interventions, such as wearable devices and mobile apps, provided additional gains in adherence and long-term efficacy. Long-term weight loss maintenance remained a difficulty. Sleeve gastrectomy combined with structured lifestyle interventions significantly improves anthropometric and health outcomes in adults. Technology-derived interventions and behavioral therapy have the potential for improving long-term weight management, but additional studies are required to optimize intervention approaches.