A new real-world study has found that bariatric surgery significantly outperforms popular weight-loss medications like semaglutide and tirzepatide, providing far greater and more sustained results for patients with obesity.
Presented at the annual meeting of the American Society for Metabolic and Bariatric Surgery (ASMBS), the study analyzed the medical records of over 63,000 adults with a body mass index (BMI) of 35 or higher. The findings show that patients who underwent bariatric procedures such as sleeve gastrectomy or gastric bypass lost about 24% of their body weight over two years—a striking contrast to the 5 to 7% average loss observed in patients prescribed GLP-1 medications over the same period.
A Gap Between Trial Results and Real-World Use
While earlier clinical trials reported weight reductions of up to 20% with GLP-1 drugs, this study suggests that such outcomes may not be consistently achievable in real-world settings. A key reason is treatment adherence: nearly 70% of patients on GLP-1 therapies discontinued the medication before the two-year mark.
“The difference in effectiveness between surgery and medication is clear and significant,” said Dr. Ann M. Rogers, President of ASMBS. “Surgery remains the most effective and durable treatment for severe obesity.”
The medications in question—semaglutide (marketed as Ozempic and Wegovy) and tirzepatide (marketed as Mounjaro and Zepbound)—have become household names in recent years due to widespread demand and celebrity endorsements. But experts caution that their long-term use comes with high costs and limited data on sustainability without continued dosage.
Cost and Commitment
Apart from lower long-term efficacy, GLP-1 drugs come at a high financial cost—estimated at approximately $1,000 per month in the United States. Meanwhile, bariatric surgery, though more invasive, is a one-time procedure often covered by insurance, and associated with additional benefits including improvements in diabetes, blood pressure, and kidney health.
“Surgical interventions should not be viewed as a last resort,” said Dr. John Morton, past president of ASMBS. “They are the gold standard for many patients, especially those who struggle to maintain adherence to pharmacologic treatment or who require faster, more significant weight reduction.”
Rethinking Treatment Paths
The study’s results are likely to reignite debate over how obesity should be treated—especially as public health systems and insurance providers weigh the costs and benefits of both options. Some experts advocate for a hybrid approach, combining pharmacological and surgical therapies tailored to the patient’s profile.
The findings also raise important questions about access. While medications can be prescribed widely, surgery requires infrastructure, trained specialists, and comprehensive aftercare—resources that are unevenly distributed.
With obesity continuing to rise globally, healthcare providers may soon have to redefine standard care models to accommodate both options more equitably. For now, the message from this study is clear: for long-term, significant weight loss, surgery still leads.