Rochester, Minnesota - Surgery to alter the digestive system is one of the most effective ways to address severe obesity. But, bariatric surgical interventions are costly, often irreversible and carry the risk of short- and long-term complications.

Doctors continue to develop new approaches to reduce risks and costs while maintaining the benefits of the surgery. The February issue of Mayo Clinic Health Letter covers the most common surgeries as well as new incision-free approaches.

Roux-en-Y gastric bypass: The most commonly performed bariatric surgery, the Roux-en-Y procedure drastically reduces the size of the stomach and allows food to bypass a segment of the small intestine. The bypass often leads to the loss of 30 to 35 percent of preoperative weight one year after the surgery and remarkable improvements in cholesterol levels and blood pressure.

Sleeve gastrectomy: The stomach is reduced from a large pouch to a tube. It restricts the amount of food that can be eaten at one time. Two years after surgery, typical weight loss is 20 to 25 percent of the presurgery body weight. A newer operation, it’s the second most commonly performed bariatric surgery.

Laparoscopic adjustable gastric banding (LAGB): An inflatable band is placed around the uppermost part of the stomach and stitched in place. The band is inflated and limits the amount of food that can be eaten. Because LAGB doesn’t involve cutting organs, it’s associated with a lower risk of death than some other surgical approaches. It has been associated with significant complications, and weight loss results generally aren’t as good as with other surgical options.

Mini-gastric bypass: This is similar to the Roux-en-Y procedure but simplifies the rearrangement of the small intestine, making it a less-complex procedure. Long-term results aren’t known yet, but research to date shows that about 95 percent of patients lose about half of their excess weight by 1.5 years after the procedure.

Endoscopic procedures: In the newest approaches to bariatric procedures, doctors make changes to the stomach and small intestine using tools inserted through the throat (endoscopically). These procedures can be performed on an outpatient basis and tend to be associated with quicker recoveries when compared to surgery. They aren’t routinely performed yet and most remain under investigation. As results and knowledge about the techniques become more widely known, it appears these endoscopic procedures will become more common. Generally, they aren’t expected to produce weight-loss results that match those of surgical procedures. Ongoing investigations are aimed at identifying what subgroups of patients might benefit most from less-invasive approaches. Candidates include those with moderate obesity, children and adolescents, or at-risk superobese individuals as a bridge to bariatric surgery.