How one teen battled obesity with medicine’s best – and most underused – tool

An important point that wasn't originally known when stomach stapling/reduction procedures were first developed:

"Shrinking the stomach can suppress the hormones that affect hunger and satiety, like the “hunger hormone” ghrelin. The gastric bypass may also reset the body’s metabolic rate, as the Biggest Loser study showed, and alter the gut microbiome in ways that make losing weight easier."

In other words, the results stem from more than just forcing the patient to meter his/her eating.