For millions seeking a solution to obesity, blockbuster injectable drugs like Wegovy and Ozempic have become a popular choice. However, a landmark new study presents compelling evidence that bariatric surgery delivers significantly more substantial and lasting results.
Direct Comparison Reveals Stark Difference
Researchers from New York University conducted the first direct, large-scale comparison between the new GLP-1 medications and permanent surgical interventions like sleeve gastrectomy and gastric bypass. Over two years, they tracked the outcomes of more than 14,000 patients who had either taken drugs such as semaglutide or tirzepatide for at least six months or undergone surgery.
The results were striking. Surgery patients lost an average of 58 pounds over two years, compared to just 12 pounds for the medication group, creating a 46-pound gap in total weight loss. In percentage terms, this translated to surgery patients losing about 26% of their total body weight, making the procedure five times more effective than the injectables in a real-world setting.
Why Surgery Offers More Durable Results
The study, presented at the American Society for Metabolic and Bariatric Surgery 2025 Annual Scientific Meeting, highlights key factors behind the disparity. Bariatric surgery is a one-time procedure that physically alters the stomach and gut, leading to transformative, long-term change. In contrast, GLP-1 drugs require expensive, lifelong monthly injections.
As many as 70% of patients stop taking the medications, often due to cost or side effects like nausea, leading to weight regain. Dr Avery Brown, surgical resident at NYU Langone Health and lead author, noted that real-world weight loss on GLP-1s is "considerably lower" than in clinical trials. "GLP-1 patients may need to adjust their expectations... or opt for metabolic and bariatric surgery to achieve desired results," he said.
Even in an ideal scenario where patients adhered perfectly to their drug regimen for two full years, surgery remained three times more effective, with patients losing 25% of body weight versus 8%.
Surgical Procedures and Long-Term Outcomes
The study examined two common surgeries. A sleeve gastrectomy removes about 80% of the stomach, reshaping it into a narrow tube to restrict food intake. A gastric bypass creates a small stomach pouch and reroutes the small intestine, limiting both food consumption and calorie absorption.
Both are highly successful, with patients typically losing 50-80% of their excess body weight. Crucially, surgery also proved superior at improving long-term blood sugar control, a vital outcome for obese patients with diabetes.
Despite its efficacy, far fewer people choose surgery annually. The study notes about 280,000 operations versus 8.4 million prescriptions each year. Dr Ann M Rogers, President of the ASMBS, which funded the research, stated: "While both patient groups lose weight, metabolic and bariatric surgery is much more effective and durable."
The findings align with previous research. A 2024 review of 20,000 patients found surgery maintained about 25% weight loss for up to a decade, while drug-induced weight loss plateaued and reversed if treatment stopped.
While surgery involves a higher upfront cost and recovery period, it represents a definitive physiological change. For many, this one-time intervention may prove more cost-effective and impactful over a lifetime than managing a costly, indefinite monthly prescription.
