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Monday, November 4, 2013

Study shows adults had significant weight loss three years after bariatric surgery

Second study in teens shows few complications in first 30 days after surgery.


National Institutes of Health-funded researchers found that adults had significant weight loss three years after bariatric surgery, with the majority losing the most weight during the first year. A separate study in teens found few incidences of complications in the first 30 days after bariatric surgery. These studies are part of the Longitudinal Assessment of Bariatric Surgery (LABS) and Teen-LABS. More than one-third of U.S. adults are obese, defined as having a body mass index or BMI of 30 or higher, and almost 17 percent of youth are also obese. Severe obesity is a BMI of 35 or more in adults and teens. BMI measures weight in relation to height.

Both studies are funded by the National Institute of Diabetes and Digestive and Kidney Diseases, part of NIH. The results appear online November 4 in the Journal of the American Medical Association (JAMA) and JAMA Pediatrics, respectively.

LABS found that adults who had either Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding had significant weight loss three years after surgery, with the majority losing the most weight during the first year. LABS is an ongoing study and its researchers will conduct longer-term follow up of participants’ health and weight status.

Teen-LABS found that 30 days after surgery short-term complications were low, which researchers view as important information to help doctors and families better evaluate the risks and benefits of the procedure. Teen-LABS investigators will continue to follow participants to determine longer-term health and weight outcomes of bariatric surgery in teens.

NIH launched LABS and Teen-LABS in 2003 and 2007, respectively, to assess the short- and longer-term risks and benefits of bariatric surgery among adults and teens with severe obesity.

LABS number NCT00465829 is supported under NIH grants U01DK066557, U01DK66667, U01DK66568, U01DK66471, U01DK66526, U01DK66585 and U01DK66555. Teen-LABS number NCT00474318 is supported under NIH grants UM1DK072493 and UM1DK095710.


Mary Horlick, M.D., project scientist for NIDDK’s Longitudinal Assessment of Bariatric Surgery and Teen-LABS in the Division of Digestive Diseases and Nutrition

The NIDDK, a component of NIH, conducts and supports research on diabetes and other endocrine and metabolic diseases; digestive diseases, nutrition and obesity; and kidney, urologic and hematologic diseases. Spanning the full spectrum of medicine and afflicting people of all ages and ethnic groups, these diseases encompass some of the most common, severe and disabling conditions affecting Americans. For more information about the NIDDK and its programs, see

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit

NIH…Turning Discovery Into Health®


Courcoulas, AP, et al. Weight change and health outcomes at 3 years after bariatric surgery among patients with severe obesity. [published online November 4, 2013]. JAMA. dol:10.1001/jama.2013.280928.

Inge, TH, et al. Perioperative outcomes of adolescents undergoing bariatric surgery: The Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. [published online November 4, 2013]. JAMA Pediatrics. dol:10.1001/jamapediatrics.2013.4296.