Efficacy of probiotic supplementation for body weight management in overweight and obese adults: a meta-analysis of randomized controlled trials predominantly from East Asia.

Background: Obesity is a major risk factor for multiple chronic diseases. Probiotics, as a novel intervention strategy for obesity, exhibit varying efficacy depending on factors such as strain, dosage, and duration of administration. This variability leads to inconsistent existing conclusions, hindering their standardized application. Methods: Seven electronic databases were searched from their inception to August 2025. The Cochrane RoB 1.0 tool was used to assess the quality of included randomized controlled trials. Statistical analysis was performed using Review Manager 5.4, and sources of heterogeneity were explored through subgroup analysis. Results: A meta-analysis of 12 randomized controlled trials demonstrated that probiotics effectively improve body weight (MD = -0.52, 95% CI - 0.90 to -0.13, Conclusion: Probiotic supplementation has a positive effect on reducing body weight, BMI, waist circumference, and body fat percentage in overweight and obese adults; however, it does not show a significant improvement in blood lipid indicators. Subgroup analysis indicates that single-strain, high-dose, and probiotic intervention plus health guidance are more effective, suggesting that probiotic interventions are both strain-specific and outcome-specific. Future large-scale randomized controlled trials should focus on strain specificity, long-term intervention effects, and cost-effectiveness. Systematic review registration: Publicly accessible website: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251123057, Registration number: CRD420251123057.