Bariatric Surgery Outperforms GLP-1 Drugs in Weight Loss After Two Years

A recent study presented at the 2025 Annual Scientific Meeting of the American Society for Metabolic and Bariatric Surgery (ASMBS) reveals that bariatric surgery, specifically sleeve gastrectomy and gastric bypass, results in significantly greater weight loss compared to GLP-1 receptor agonists, such as semaglutide and tirzepatide, over a two-year period. Conducted by researchers from NYU Langone Health and NYC Health + Hospitals, the study analyzed real-world electronic medical records of patients with a body mass index (BMI) of at least 35 who underwent either bariatric surgery or received GLP-1 prescriptions between 2018 and 2024.

According to the findings, patients who had undergone bariatric surgery lost an average of 58 pounds, translating to a 24% total weight loss. In contrast, individuals receiving GLP-1 therapy for at least six months achieved an average weight loss of only 12 pounds, or 4.7%. Further analysis indicated that while continuous GLP-1 treatment for a full year can yield more weight loss, it remains substantially lower than that achieved through surgical interventions.

Dr. Avery Brown, the lead author of the study and a surgical resident at NYU Langone Health, highlighted that adherence to GLP-1 therapy is a considerable challenge, with approximately 70% of patients discontinuing treatment within one year. "GLP-1 patients may need to adjust their expectations, adhere more closely to treatment, or opt for metabolic and bariatric surgery to achieve desired results," Dr. Brown stated.

The retrospective comparative effectiveness study utilized data from a cohort of 51,085 patients, comparing the outcomes of those who underwent bariatric surgery against those prescribed GLP-1 therapies. The research was supported by a grant from the National Institutes of Health (NIH).

Senior author Dr. Karan R. Chhabra, Assistant Professor of Surgery and Population Health at NYU Grossman School of Medicine, emphasized the need for future studies to optimize GLP-1 outcomes and identify which patients are better suited for bariatric surgery versus pharmaceutical treatments.

Despite the effectiveness of bariatric surgery, its utilization remains low. According to the ASMBS, only about 270,000 metabolic and bariatric procedures were performed in the United States in 2023, representing roughly 1% of those eligible based on BMI criteria. ASMBS President Dr. Ann M. Rogers reiterated the importance of considering bariatric surgery for patients who struggle with weight loss through GLP-1 therapies or experience side effects.

The implications of obesity are far-reaching, with the Centers for Disease Control and Prevention (CDC) reporting that 40.3% of Americans are classified as obese, and approximately 9.4% as severely obese. This condition is linked to numerous health risks, including cardiovascular disease, type 2 diabetes, and certain cancers.

In summary, while GLP-1 drugs represent a non-surgical option for weight loss, the current study underscores the superior efficacy and durability of bariatric surgery. As healthcare providers seek to improve treatment outcomes for obesity, understanding the full spectrum of intervention options will be critical in addressing this public health crisis effectively.