Real-world GLP-1 results fall short of clinical trials compared to surgery
Weight-loss surgery has been shown to be significantly more effective than popular GLP-1 receptor agonists when it comes to shedding pounds, according to a recent study presented at the American Society for Metabolic and Bariatric Surgery (ASMBS) 2025 Annual Scientific Meeting. The study, which analyzed “real-world” electronic medical record data of 51,085 patients at NYU Langone Health and NYC Health + Hospitals, found that patients who underwent bariatric surgery experienced five times more weight loss compared to those who were prescribed injectable semaglutide or tirzepatide.
The patients in the study all had a body mass index (BMI) of at least 35 and had either undergone sleeve gastrectomy or Roux en-Y gastric bypass surgeries, or were prescribed GLP-1 receptor agonists between 2018 and 2024. Sleeve gastrectomy involves reducing the size of the stomach to aid in weight loss, while gastric bypass reroutes the digestive tract to bypass a portion of the small intestine.
The results showed that patients who had bariatric surgery lost an average of 58 pounds two years later, while those who took GLP-1 medications for at least six months only lost 12 pounds. The surgical outcomes marked a 24% total weight loss compared to a 4.7% weight loss for patients on injectable medications.
Despite clinical trials showing weight loss between 15% and 21% for GLP-1s, the study found that weight loss in the real world was considerably lower, even for patients who were on active prescriptions for an entire year. Lead study author Avery Brown, MD, a surgical resident at NYU Langone Health, noted that as many as 70% of patients with GLP-1 prescriptions may discontinue treatment within one year.
The prevalence of GLP-1 drugs is higher than that of bariatric surgeries, with studies showing that around 12% of Americans have taken a GLP-1 medication, while only 6% are currently taking them. However, more than half of patients stop taking GLP-1 medications after one year, and 72% abandon them after two years.
The study, which received grant funding from the National Institutes of Health (NIH), aims to explore strategies for improving outcomes for patients taking GLP-1s and identifying which patients are better candidates for surgery versus injectable medications.
In conclusion, the study underscores the effectiveness of weight-loss surgery compared to GLP-1 medications, highlighting the importance of personalized treatment plans for patients struggling with obesity. Further research and intervention strategies are needed to address the challenges faced by patients on injectable medications and to improve long-term weight loss outcomes.
