4200 Northside Pkwy, Bldg 8, Ste 200
Atlanta, GA 30327
Gastric bypass surgery often leads to a sustained weight loss, and now researchers have found that this is explained in part by how the operation enhances energy expenditure.
Reduced caloric intake does not provide the entire explanation for the success of gastric bypass patients at keeping the pounds off over the long haul.
The study, published in PLOS ONE, showed that gastric bypass surgery causes energy expenditure to increase at mealtime.
“Parts of the small intestine become more active and require additional nutrition after a gastric bypass,” said Malin Werling, MD, University of Gothenburg, Gothenburg, Sweden. “As a result, the blood absorbs fewer nutrients to store as fat. You might say that people burn calories by eating.”
The study examined patients by means of a metabolic chamber before and up to 2 years after surgery. Subjects spent 24 hours in the chamber, which was furnished like a small hotel room, in order for researchers to study their metabolism in detail.
The increase in the body’s energy requirements after meals is well-established. The gastrointestinal tract needs energy to break down and absorb nutrients. The researchers had not realised that gastric bypass surgery reinforces this process to such an extent that it contributes to preserved weight loss.
Additional studies will trace the specific mechanisms that generate the greater meal associated energy requirements after such operations. Researchers hope that the process can one day be augmented by means of drugs such that surgery does not have to be performed as often.
SOURCE: University of Gothenburg