Does reduction in gastric acid secretion in bariatric surgery increase diet-induced thermogenesis?
GROUND: Patients who have undergone gastrectomy for benign ulcer do not develop obesity. Furthermore, morbidly obese patients who undergo biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGBP) and vertical banded gastroplasty (VBG) plus truncal vagotomy, may lose more weight compared with patients who undergo VBG alone. A common characteristic of the above is the reduction of gastric hydrochloric acid secretion. We investigated whether reduction in gastric acid increases dietary-induced thermogenesis because of maldigestion of foods, and this may account for the greater weight loss in the above situations. MATERIALS AND METHODS: 22 volunteers without symptoms from the upper gastrointestinal tract were studied. Gastric pH was measured and resting energy expenditure (MREE), using indirect calorimetry, was determined before and 8 hours after consumption of a standard meal. Parameters were measured again after 2 months administration of proton pump inhibitors in all volunteers.
