Comparing weight-loss tools: How bariatric surgery differs from GLP-1 agonists

Doctor and patient discussing weight loss

Every day, it seems like more people are using new weight-loss drugs to lose weight. The main ingredient, semaglutide, is one of several GLP-1 (glucagon-like peptide-1) agonists on the market. These mimic a hormone your small intestine makes to slow digestion and help you feel fuller longer.

Originally prescribed to manage type 2 diabetes, GLP-1 agonists are now in high demand as a weight-loss tool, requiring a weekly or daily self-injection.

If you have a body mass index (BMI) of 40 or greater, or a BMI of 35 and at least one weight-related comorbidity (existing medical condition) like sleep apnea or diabetes, you may be debating whether to take a GLP-1 agonist or have bariatric surgery. Both approaches share similar criteria, though medication requirements are lower (BMI of 30 or greater, or 25 with a comorbidity). So, which is the better option?

Bariatric surgery: a first-line treatment that's safer than ever

"It's impotant that we get away from this concept that bariatric surgery is something that's reserved for patients who are at the extremes of obesity or have failed medical weight loss," says Samantha Witte, MD, a bariatric surgeon at Main Line Health.

"What's becoming more and more obvious with data in the last five to 10 years is that bariatric surgery is the best long-term solution for patients with obesity, even at a moderate level," she says.

Bariatric surgery has a 40-year track record proving it's safe and effective. The procedure has also been refined over the years using the latest surgical advances. It's now performed using minimally invasive techniques (including robotic assistance), resulting in less pain and fewer complications and requiring only an overnight hospital stay.

"The mortality risk for bariatric surgery is lower than hip replacement or gallbladder surgery," says Richard Ing, MD, a bariatric surgeon and medical director of the bariatric surgery program at Main Line Health.

Bariatric surgery and GLP-1 agonists both come with the risk of side effects. One big difference is that the long-term effects of bariatric surgery are well established, while no long-term data exists on injectables since they're so new.

"The data we already have suggests that the efficacy (of injectables) is only maintained when the dose is maintained," says Dr. Witte. In other words, if you stop the medication, you'll likely regain any weight you lost.

Committing to a healthy lifestyle

With bariatric surgery, the procedure itself is only the beginning of what's required. You'll need to make and sustain lifestyle modifications, including healthy eating and exercise, in order to keep off the weight. Main Line Health's Comprehensive Weight and Wellness Program provides lifelong coaching and support from a team of experts.

Dr. Witte says the patients who are successful on GLP-1 agonists are also dieting, exercising and making healthy lifestyle changes.

A surprising effect of bariatric surgery

During bariatric surgery, the surgeon changes the shape of your stomach so you'll eat less and sometimes bypasses part of the intestines so you'll absorb fewer calories. This also causes physiological changes to your brain and gut that resets your metabolism. Your body will no longer increase your appetite or slow your metabolism in order to maintain a specific weight (your "set point").

"We found that the surgery actually alters all gut hormones, which has a much more powerful effect than the changes of a smaller stomach or less absorptive capacity," Dr. Ing says.

While it's not understood exactly why this happens, we know these gut hormones work together to control hunger and fullness to a higher degree than any single hormone such as GLP-1.

Health improvement beyond weight loss

There's no question GLP-1 agonists can help people lose weight and may also reduce cardiac disease.

Bariatric surgery helps people lose more weight than any other treatment. More importantly, it resolves a long list of chronic illnesses. Heart disease, diabetes, hypertension, sleep apnea, high cholesterol and other conditions have been shown to improve by as much as 50-95% after bariatric surgery.

Dr. Ing says people are getting off insulin and other medications and no longer need CPAP machines, whereas people who use GLP-1 agonists are adding another medication they'll need to continue taking.

Bariatric surgery also prevents future health problems such as heart disease, stroke, cancer and diabetes. According to the American Society for Metabolic & Bariatric Surgery, studies have shown that weight-loss surgery can lower a person's risk of death from any cause by over 40%.

A strong support system is vital for achieving your objectives concerning bariatric surgery and weight loss. To ensure success, our Comprehensive Weight and Wellness Program offers preoperative, long-term and post-op care. All procedures are conducted by experienced bariatric surgeons certified by the American Board of Surgery, so you know you're in good hands.

Next steps:

Make an appointment with a bariatric surgery provider
Learn more about bariatric surgery at Main Line Health
Register for a weight loss webinar
Weight loss surgery: fact vs. fiction

well ahead logo Content you want, delivered to your inbox

Want to get the latest health and wellness articles delivered right to your inbox? 

Subscribe to the Well Ahead Newsletter.

Man smiling looking at his phone