Study Finds Weight Loss Drugs Like Ozempic Aren't As Effective As This One Strategy

Obesity affects around four out of every 10 adults in the United States, according to the Centers for Disease Control and Prevention. But the recent emergence of GLP-1 agonist drugs, including Ozempic and Wegovy, has brought new weight loss options to people who have obesity but aren't making inroads with lifestyle changes alone. (It's worth noting, though, that Ozempic has increased risks for people over 50.)

GLP-1 agonists "trick" the body into feeling fuller, resulting in satiety after modest food intake. As a result, people who respond to these medications end up shedding pounds. In a 2024 study published in Obesity that examined 2,405 patients with obesity (or overweight) and type 2 diabetes, about 33% lost at least 5% of their weight after taking a GLP-1 agonist for 72 weeks. Not surprisingly, prescriptions for GLP-1 agonists have risen dramatically. From 2018 to 2023, GLP-1 agonist sales reached $15 billion in the United States (via Pew Research).

Yet for all their potential, GLP-1 agonists may not be the most effective way for people with BMIs of 35 or greater to lose weight quickly. Instead, a rather conventional strategy still reigns as a proven weight loss treatment: bariatric surgery.

There are several kinds of bariatric surgery procedures, including constricting the amount of food that can enter the stomach, removing most of the stomach, and rerouting food past most of the upper intestine. However, bariatric surgery seeks to reduce food intake amount and absorption through the manipulation of the way the digestive tract works. (Read about foods you can't eat after bariatric surgery.)

How much more effective is bariatric surgery than GLP-1 agonists? A 2025 study in the Surgery for Obesity and Related Diseases looked at long-term weight loss patient data from 14,152 individuals who had either had bariatric surgery or consistently used a GLP-1 agonist. The results showed that people who opted for bariatric surgery nearly quintupled their weight loss compared to their counterparts who were prescribed a GLP-1 agonist.

One possible reason for this outcome might be the permanency of most bariatric surgery, as it's rarely reversible. Therefore, patients have no control over how their digestive systems work, including how long it takes to digest food. In contrast, someone taking a GLP-1 agonist can stop, making it possible to regain the lost weight. In fact, a 2024 study in the Journal of Managed Care and Specialty Pharmacy revealed that just one out of three people who were prescribed GLP-1 agonists were still using their drugs one year later.

That said, both obesity treatments come with practical roadblocks. Specifically, the high cost of both GLP-1 agonists and bariatric surgery can be a barrier for many people who would like help to lose weight. 

GLP-1 agonists are typically $900 and up for a one-month supply when purchased out of pocket. And even though some states have mandated that insurance companies and Medicaid cover the cost of GLP-1 agonists, not all states do.

The price tag for bariatric surgery is even higher, sitting at between roughly $17,000 and $26,000 depending on the procedure performed. However, proponents claim that patients who have obesity can recoup the expense in a few years since paying for healthcare (and conditions that frequently co-occur with obesity, like diabetes and heart disease) is lower for people who maintain a healthy weight based on age, gender, body type, and medical history.