The Effectiveness of Nonsurgical Interventions for Weight Loss Maintenance in Adults: An Updated, GRADE-Assessed Systematic Review and Meta-Analysis of Randomized Clinical Trials

Context: Today, there are many discussions about the best way to maintain weight and prevent weight regain after a period of weight loss.

Objectives: The aim of this study was to summarize, based on data from randomized clinical trials (RCTs), the impact of nonsurgical interventions for adults' weight loss maintenance.

Data sources: The Medline (PubMed), Scopus, and Web of Science databases were reviewed during June 2023.

Data extraction: Meta-analyses assessing the impacts of nonsurgical interventions for weight loss maintenance were conducted. Effect sizes of nutritional interventions were recalculated by applying a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation framework was implemented to determine evidence certainty.

Results: Meta-analysis of data from a total of 56 RCTs (n = 13 270 participants) represented a significant weight reduction after behavior and lifestyle interventions (mean difference [MD], -0.64 kg [95% CI, -1.18 to -0.09]; I2 = 89.5%; P < .001 for heterogeneity). Pharmacological interventions had also a significant effect on weight change during the weight maintenance phase (MD, -2.57 kg [95% CI, -3.12 to -2.02]; I2 = 91.6%; P < .001 for heterogeneity). The weight loss reduction from pharmacological interventions was greater with sibutramine (MD, -2.57; 95% CI: -3.12 to -2.02). Additionally, diet intervention and dietary and physical activity strategies were associated with a negligible trending decrease in weigh regain (respectively: MD, -0.91 kg [95% CI, -2.18 to 0.36], I2 = 55.7%, P = .016 for heterogeneity; and MD, -0.3 kg [95% CI, -4.13 to 3.52], I2 = 94.1%, P < .001).

Conclusion: The findings of this review indicate there is a favorable impact of behavior-based interventions and antiobesity medications on weight maintenance.

Systematic review registration: PROSPERO registration no CRD42023468056.