The Evolution of Metabolic-Bariatric Surgery

by Sheetal Nijhawan-Long, MD; and John Scott, MD, FACS, FASMBS

Spring 2025

The field of metabolic-bariatric surgery has evolved greatly over the years. What started as large, open surgeries has now advanced to minimally invasive procedures using tiny cameras (laparoscopic surgery) and even robotic technology. Surgeons continue to innovate to make these surgeries safer and more effective. Thanks to ongoing research and new technology, earlier procedures have been improved, and new ones have been created to help the body regulate weight using natural hormones.

A Brief History

Metabolic-bariatric surgery has been around for decades. Early procedures, like intestinal bypasses and open gastric bypasses in the 1960s, helped patients lose a lot of weight but came with serious risks. These surgeries were lengthy, required large incisions and often caused complications. Because of this, many healthcare providers were hesitant to recommend them.

In 1994, Dr. Alan Wittgrove performed the first laparoscopic gastric bypass using small incisions and a camera. This made the surgery much safer and helped it become more common.

Since then, metabolic-bariatric surgery has continued to improve, focusing on treating the root causes of obesity while keeping patients safe. Robotic technology has also made procedures more precise, attracting a new generation of surgeons eager to use the latest tools to help patients.

Today’s Leading Procedures

Today, the two most common metabolic-bariatric surgeries in the U.S. are the Roux-en-Y gastric bypass (RYGB) and the vertical sleeve gastrectomy (VSG). Together, these make up the majority of surgeries performed in hospitals and outpatient centers. But what does the future hold for metabolic-bariatric surgery?

One promising option is a modern version of an older technique. The Single Anastomosis Duodeno-Ileostomy (SADI) is based on the Duodenal Switch, which is powerful but less common. SADI provides excellent long-term weight loss and improves type 2 diabetes (T2D), with safety similar to other popular surgeries. What sets SADI apart from gastric bypass (RYGB) is the section of the intestine it bypasses, offering a unique set of risks and benefits.

Another option gaining attention is the One-Anastomosis Gastric Bypass (OAGB). This surgery creates a long, narrow stomach pouch and connects it to a loop of the small intestine using only one surgical connection. Unlike SADI, OAGB connects the stomach to the intestine, not two parts of the intestine. Because it’s a simpler surgery, OAGB can be done quicker than traditional gastric bypass, but it has a risk of bile reflux.

The Future of Innovation

In addition to robotic-assisted surgery, another exciting development is the use of magnets to join sections of the intestine without staples or stitches. Dr. Michel Gagner was the first to use this method in a SADI procedure. Magnets are placed across two sections of the intestine, and over several weeks, the tissue between them dissolves while the edges heal together. The magnets are then naturally expelled, leaving nothing behind.

By avoiding sutures or staples, this approach can reduce surgery time and lower the risk of leaks or infections. Magnets are also being explored for other types of surgery. In December 2023, Dr. Matthew Kroh at the Cleveland Clinic used an internal magnet to reposition organs during surgery, minimizing the number of incisions needed. As this technology grows, it could change how many surgeries are done.

Surgery, Medications and the Future of Care

While metabolic-bariatric surgery has become safer and more effective, medications for obesity have also advanced. New drugs, like GLP-1 receptor agonists and other anti-obesity medications, are now more accessible than ever. Still, research shows that metabolic-bariatric surgery remains the most effective long-term treatment for obesity.

Surgery is also often more cost-effective over time and easier for many patients to tolerate than medications, which can be expensive and cause side effects that lead some people to discontinue use.

Obesity is a chronic disease that needs ongoing care—there’s no one-time cure. Like other chronic conditions such as cancer or heart disease, obesity requires comprehensive treatment. Surgery, medications and lifestyle changes all work together. While some people regain weight after surgery, options are available to help them. Just as cancer patients may need more treatments if their disease returns, people with obesity can get additional medical or surgical care when needed.

Since 2010, vertical sleeve gastrectomy (VSG) has been the most common metabolic-bariatric surgery in the U.S., with more than 150,000 procedures each year. Most patients are happy with their results, but some regain weight or develop acid reflux. Fortunately, there are effective solutions. SADI and OAGB are great revision options for people who need extra help with weight management. Gastric bypass is often the preferred choice for treating acid reflux. Many bariatric surgeons specialize in these revision surgeries to help patients reach their health and weight goals.

Role of Surgeons

Bariatric surgeons do more than just operate. They also contribute to research, education and advocacy for people living with obesity. Their work includes advancing obesity treatments, improving access to care and promoting better health outcomes.

As the field evolves, many professionals remain focused on improving surgical techniques, exploring new approaches and supporting patients on their health journeys. Metabolic-bariatric surgery continues to be a powerful tool for improving health and changing lives.

About the Authors:

Sheetal Nijhawan-Long, MD, is a board-certified surgeon and the Medical Director for the Center for Weight Control at Sharon Regional. She is a fellow of the ACS and FASMBS, holds a Focused Practice Designation in Bariatric Surgery and is a Diplomate of the American Board of Obesity Medicine.

John Scott, MD, FACS, FASMBS, is the Director of the bariatric surgery program and chief of the Minimal Access and Bariatric Surgery division at Prisma Health. He is also a clinical professor of surgery at the University of South Carolina School of Medicine Greenville. Dr. Scott serves on multiple national boards, including ASMBS, ObesityPAC and the OAC, and is active in surgical education, research and advocacy.

Related Resources

PREVIOUS

How to Eat Well and Feel Your Best on GLP-1 Medications

NEXT

Obesity and Eating Disorders: A Patient and Provider Perspective