Weight-loss surgery has lasting benefits in teens

Weight-loss surgery has proven to have significant benefits for adolescents with severe obesity. Dmytro Zinkevych / Shutterstock

About 1 in 5 adolescents in the U.S. has obesity. Obesity increases the chances of having other serious health problems. These include heart disease, type 2 diabetes, and certain cancers. Lifestyle changes, such as physical activity and dietary changes, are often the first choice for treating childhood obesity. If that doesn’t work, medications or weight-loss surgery, also called metabolic and bariatric surgery, may also be considered. But the long-term effects of weight-loss surgery on adolescents are not well known.

To learn more, a multi-center research group launched an NIH-supported clinical study in 2007. It aims to assess the safety and effectiveness of weight-loss surgery among teens who have severe obesity. Severe obesity is defined in teens as having a body mass index (BMI, a ratio of weight to height) of 35 or more.

The study enrolled 260 teens who had bariatric surgery at six clinical centers. They received either gastric bypass (161 participants) or sleeve gastrectomy (99 participants). Their average age was 17. Health-related data were collected within 30 days before each operation and then at various intervals until about 10 years after surgery. Results were published in the New England Journal of Medicine on October 31, 2024.

Overall, the researchers found that participants’ BMI declined significantly within the first year after surgery and remained low a decade later. Results were similar regardless of the type of surgery. After 10 years, participants had an average 20% reduction in BMI. Those who had greater early weight loss, within six months after surgery, tended to have a more beneficial long-term decline in BMI after 10 years.

In addition, many preexisting conditions at the start of the study were no longer present a decade later. For instance, 57% of those who had hypertension before surgery no longer did after 10 years. Likewise, 54% of those with abnormal cholesterol (dyslipidemia) and 55% of those with type 2 diabetes didn’t have those conditions 10 years later.

The researchers note that the 55% reduction in type 2 diabetes was much better than the rates seen in adults after weight-loss surgery in a separate NIH-supported study. That study found that only 18% of adults remained diabetes-free seven years after weight-loss surgery and only 13% were without diabetes 12 years after surgery.

“This is considerably better than the outcomes reported in people who underwent bariatric surgery as adults, a major reason why treating obesity seriously in adolescents is so important,” says study first author Dr. Justin R. Ryder of the Lurie Children’s Hospital of Chicago. “Our study…validates bariatric surgery as a safe and effective long-term obesity management strategy.”

The researchers note that further studies are needed to compare health outcomes after surgery versus weight loss medication for teens with severe obesity.