Surgery Beats Popular Weight Loss Drugs by 5 Times—Here's What the Data Shows

Bariatric surgery dramatically outperforms popular weight loss medications like Ozempic and Wegovy in real-world settings, with patients losing about five times more weight over two years. A major study comparing over 51,000 patients found that those who underwent sleeve gastrectomy or gastric bypass lost an average of 58 pounds, while those using GLP-1 receptor agonist drugs like semaglutide or tirzepatide lost only about 12 pounds.

How Do Real-World Results Compare to Clinical Trials?

The gap between laboratory promise and everyday reality is striking. While clinical trials show weight loss between 15% to 21% for GLP-1 drugs, this real-world study found much smaller results—even among patients who stayed on the medications for a full year, average weight loss reached only 7%. Surgery patients, meanwhile, achieved 24% total weight loss compared with just 4.7% for those using medication.

"Clinical trials show weight loss between 15% to 21% for GLP-1s, but this study suggests that weight loss in the real world is considerably lower even for patients who have active prescriptions for an entire year," said lead author Dr. Avery Brown, a surgical resident at NYU Langone Health.

What Makes GLP-1 Drugs Less Effective in Practice?

Several real-world challenges appear to limit the effectiveness of these popular injectable medications. The study, conducted by researchers at NYU Langone Health and NYC Health + Hospitals, revealed significant barriers that don't exist in controlled clinical trials.

• High Dropout Rates: As many as 70% of patients may discontinue GLP-1 treatment within one year, with 53.6% stopping within the first year and 72.2% quitting by two years
• Side Effects: Patients often struggle with nausea, digestive issues, and other adverse reactions that make long-term adherence difficult
• Cost Barriers: Out-of-pocket expenses can make sustained treatment financially challenging for many patients
• Long-term Adherence: Unlike surgery, which provides permanent anatomical changes, medications require ongoing commitment and lifestyle management

The researchers analyzed electronic medical record data from patients treated between 2018 and 2024, focusing on those with a body mass index (BMI) of at least 35—roughly 245 pounds for someone 5'10" tall. After adjusting for factors like age, BMI, and existing health conditions, they compared outcomes across 51,085 patients in both treatment groups.

Why Does Surgery Provide More Lasting Results?

Bariatric procedures create permanent physical changes that help patients maintain weight loss long-term. The study included sleeve gastrectomy, which removes about 80% of the stomach, and Roux-en-Y gastric bypass, which creates a small stomach pouch and reroutes part of the small intestine.

"While both patient groups lose weight, metabolic and bariatric surgery is much more effective and durable," said Dr. Ann M. Rogers, President of the American Society for Metabolic and Bariatric Surgery, who was not involved in the study. "Those who get insufficient weight loss with GLP-1s or have challenges complying with treatment due to side effects or costs, should consider bariatric surgery as an option or even in combination."

Despite these impressive results, bariatric surgery remains significantly underused. More than 270,000 metabolic and bariatric procedures were performed in 2023, representing only about 1% of people who meet BMI eligibility criteria. This suggests millions of Americans who could benefit from surgery are instead relying on less effective medication-based approaches.

The findings highlight an important reality check for the estimated 12% of Americans who have tried GLP-1 drugs and the 6% currently using them. Senior author Dr. Karan R. Chhabra, a bariatric surgeon at NYU Grossman School of Medicine, noted that future research will focus on optimizing GLP-1 outcomes and identifying which patients might be better candidates for surgery versus medications.