Gastric bypass surgery may decrease the urge to eat when not hungry

Scientists are finding that gastric bypass surgery may change more than a person’s weight -- hormones secreted in the gut could affect some eating habits. A new study finds that the surgery may tamp down the desire to eat when not hungry.

The study, published in the Aug. 1 issue of the American Journal of Clinical Nutrition, focused on hedonic hunger, or the urge to eat highly palatable foods when not hungry. Among the study participants were 123 obese patients, 136 people who had gastric bypass surgery and a control group made up of 110 people who were not obese. Those who had undergone bypass surgery had lost an average of about 106 pounds and about 18 body mass index points from their starting weight.

Test subjects filled out a Power of Food Scale questionnaire, which measures one’s appetite for appetizing foods, but not the consumption of them. Questions included “I find myself thinking about food even when I’m not physically hungry,” “If I see or smell a food I like, I get a powerful urge to have some” and “When I eat delicious food I focus a lot on how good it tastes.”

Those in the obese group had significantly higher scores than those who had had gastric bypass surgery, and the scores of the gastric bypass surgery group were on par with the non-obese control group.

Though the study did not delve into the mechanism that may change hedonic hunger in gastric bypass patients, researchers speculate that the decreased desire to eat tasty foods could be due to alterations in gastrointestinal hormones, or because of behavioral changes after surgery -- eating rich and fatty foods can lead to abdominal pain and other problems, so people might have an aversion to those foods.

-- Jeannine Stein