It’s the exact opposite.” The number of teenagers who underwent bariatric surgery more than doubled nationwide between 2010 and 2017 and continues to rise. Seeley emphasizes that weight loss doesn’t simply result from a newly tiny stomach that limits how much people can eat. The crucial roles instead seem to be played by bile acids and antimicrobial peptides in the gut, each of which increase markedly after surgery; Seeley is still sorting out the exact mechanisms of their influence. “Why bariatric surgery works so well is because you’re changing lots of things at the same time,” Seeley says. Most important, bariatric surgery seems to reset, to a lower bound, the body weight that the brain tries to maintain.

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Persons: Rodriguez, “, ”, Alexandra, ” Gabriela, ” Rodriguez, Thomas Inge, Randy Seeley, Seeley, ” Seeley, “ I’m, ” Inge, I’d, “ We’ve Organizations: Teen, National Institutes of Health, Lurie Children’s Hospital, University of Michigan Locations: United States, Chicago