Efficacy of Metformin in Weight Management and Glycemic Control in Type 2 Diabetes: An Updated Systematic Review and Meta-analysis

Introduction: Type 2 diabetes mellitus (T2DM) is a chronic condition where obesity plays a key role. Metformin is commonly used to manage T2DM, with benefits in both glycemic control and weight management. This systematic review and meta-analysis update the evidence on metformin’s impact on weight loss and glycemic control in T2DM patients. Objective: To assess metformin’s efficacy in reducing body weight and improving glycemic control in T2DM patients by synthesizing recent studies. Methods: Following PRISMA guidelines, relevant studies were identified in PubMed, EMBASE, and clinicaltrials.gov. Fourteen randomized controlled trials and cohort studies, involving 11,686 T2DM patients, were analyzed using RevMan 5.4 software. Results: Metformin led to a modest but significant reduction in body weight (Mean difference = 0.16; 95% CI: 0.69 to 1.02, p<0.00001) and significantly lowered glycosylated hemoglobin (A1C) and fasting plasma glucose (FPG) levels. Despite some study heterogeneity, the risk of bias was minimal. Conclusions: Metformin is effective in modest weight reduction and significant glycemic control in T2DM patients, supporting its use as first-line therapy, especially for those who are overweight or obese.