Which Works Better for Weight Loss—Surgery or Injections?

Weight loss injections like Ozempic®, Wegovy®, and Mounjaro® have skyrocketed in popularity. But a new 2025 study suggests these medications may not be as effective in the real world as many people believe—especially when compared to bariatric surgery.

Researchers at NYU Langone Health analyzed over 51,000 patient records and found that bariatric surgery was five times more effective than GLP-1 injections for sustained weight loss.

If you’ve been wondering whether you should keep trying weekly injections or explore weight loss surgery, here’s what the science—and our experience at BASS—has to say.

The Numbers: Weight Loss Surgery vs GLP-1 Injections

The study, presented at the 2025 ASMBS (American Society for Metabolic and Bariatric Surgery) Annual Scientific Meeting, reviewed outcomes from patients with a BMI of 35 or higher who either:

• Had bariatric surgery (sleeve gastrectomy or gastric bypass)
• Or were prescribed GLP-1 receptor agonists like semaglutide or tirzepatide

Results after 2 years:

While clinical trials often show 15–21% weight loss with GLP-1s, real-world results are typically lower. The study also found that up to 70% of patients stopped taking their injection within the first year.

Why Bariatric Surgery Has the Edge

Weight loss surgery is not just about shedding pounds. It’s a metabolic reset that improves or even reverses obesity-related conditions like:

• Type 2 diabetes
• High blood pressure
• Sleep apnea
• High cholesterol

Surgery also restructures the digestive system, helping regulate hunger hormones and reduce long-term cravings—unlike medications that require ongoing use to be effective.

Many patients at the BASS Bariatric Surgery Center report improvements in energy, mobility, and confidence that injections alone couldn’t deliver.

Is Weight Loss Surgery Right for You?

You might be a candidate for bariatric surgery if you:

• Have a BMI of 35+ (or 30+ with a serious health condition)
• Are struggling with yo-yo dieting or medication side effects
• Want a long-term solution, not a short-term fix
• Are ready to commit to lifestyle changes with support

Only 1% of eligible patients currently undergo bariatric surgery, according to ASMBS. That means many people are missing out on a life-changing solution—often due to stigma or outdated perceptions.

GLP-1 Medications Still Have a Role

GLP-1 medications like Ozempic and Mounjaro can still be effective tools, especially for those:

• Who aren’t ready for surgery
• Who want to lose a modest amount of weight
• Or who are preparing for surgery by losing weight beforehand

At BASS, we take a personalized approach—sometimes combining medications with surgical planning to help patients succeed at every stage.

Take the First Step Toward a Healthier You

If you’ve tried everything—from diets to injections—and still aren’t where you want to be, it might be time to explore a more effective, sustainable path to weight loss.

Schedule a consultation with the BASS Bariatric Surgery Center in Walnut Creek, Califonrnia, today. Our experienced team will walk you through your options, answer your questions, and help you take control of your health.