Obese people who underwent gastric bypass surgery may lose weight faster as the levels of a hormone known to stimulate hunger fall after the operation is made, researchers claim in a study published in the July issue of The Archives of Surgery journal.
The hormone, ghrelin, is released into the bloodstream from the stomach and upper intestine and is among two dozen hormones thought to help regulate hunger
Edward Lin, D.O., and colleagues at Emory University, Atlanta, conducted a study to determine if early alternations in ghrelin levels in severely obese patients undergoing weight reduction surgery may be attributed to gastric partitioning. The study included 42 patients who were morbidly obese, with a body mass index (BMI) of 40 or higher, and six lean control patients. (BMI is calculated as weight in kilograms divided by the square of height in meters.)
Thirty-four patients underwent Roux-en-Y gastric bypass (RYGB), a procedure in which the stomach is divided to create a pouch out of the smaller proximal (near) portion of the stomach, and then attached to the small intestine, bypassing a large part of the stomach and all of the duodenum. Eight patients underwent other gastric procedures that did not involve complete division of the stomach. Six non-obese patients undergoing anti-reflux surgery served as lean controls. The researchers measured ghrelin levels in blood plasma samples at different stages of surgical intervention.
"A divided gastroplasty creating a small proximal gastric pouch results in significant early declines in circulating ghrelin levels that are not observed with other gastric procedures," they report.