A large network meta-analysis finds metabolic bariatric surgery most effective for weight loss across obesity classes, with tirzepatide leading among medications.
4 BMI classes comparedFirst network meta-analysis spanning overweight through class III obesity across all treatment types
What the researchers found
Across all BMI classes, metabolic bariatric surgery produced the greatest weight loss, but newer obesity medications including tirzepatide significantly narrowed the efficacy gap compared to surgical interventions.
Why it matters
This is one of the first analyses to compare all approved obesity treatment categories head-to-head across BMI classes, helping clinicians match treatments to patient needs.
How the study worked
Systematic review and network meta-analysis of randomized controlled trials comparing obesity management medications, endoscopic bariatric procedures, and metabolic bariatric surgery vs lifestyle/placebo across BMI classes.
What this study cannot tell us
Network meta-analysis relies on indirect comparisons across trials with different populations and follow-up periods. EMA-approved treatments may differ from those approved in other regions.
How to read the evidence
Network meta-analysis of RCTs — high-quality evidence synthesis, though limited by indirect comparisons across heterogeneous trials.
When this study was published
Published in 2026; includes the latest obesity medications and surgical techniques.
The bigger picture
As GLP-1 and dual agonist medications continue to improve, the traditional treatment escalation model (lifestyle → drugs → surgery) may need to be reconsidered, with medications becoming viable alternatives to surgery for some patients.
Questions still open
- At what BMI threshold do medications become comparable to surgery in long-term outcomes?
- How do costs and quality-of-life measures compare across these treatment categories?
Common questions
Which obesity treatment works best?
Should I choose medication or surgery for obesity?
Read the original research
Efficacy and safety of European Medicines Agency (EMA)-approved pharmacological, endoscopic, and surgical treatments in different classes of obesity: A network meta-analysis of randomised controlled trials for the development of the SIO (Società Italiana Obesità) Italian guidelines for the diagnosis and treatment of overweight and obesity.
Diabetes, obesity & metabolism, 28(1), 358-378
Citation
Barazzoni, Rocco; Monami, Matteo; Buscemi, Silvio; Busetto, Luca; De Luca, Maurizio; Navarra, Giuseppe; Ragghianti, Benedetta; Silverii, Giovanni Antonio; Belluzzi, Amanda; Mannucci, Edoardo; Sbraccia, Paolo. (2026). Efficacy and safety of European Medicines Agency (EMA)-approved pharmacological, endoscopic, and surgical treatments in different classes of obesity: A network meta-analysis of randomised controlled trials for the development of the SIO (Società Italiana Obesità) Italian guidelines for the diagnosis and treatment of overweight and obesity.. Diabetes, obesity & metabolism, 28(1), 358-378. https://doi.org/10.1111/dom.70204