Background: Inadequate protein intake is a concern following Roux-en-Y gastric bypass (RYGBP). The small gastric pouch and bypass restrict energy intake and may lead to insufficient protein intake and absorption, and excess loss of lean tissue. Methods: We evaluated protein intake in 93 (77 F, 16 M) morbidly obese individuals (BMI = 52.0±12.9 [SD]) who underwent RYGBP at our medical center. Participants completed 24-hr food recalls and received nutritional counseling at 3, 6, and 12 months following surgery. Results: Daily energy intake (kcal/day) increased from 849±329 (SD) at 3 months to 1,101±400 at 12 months (P=.009). Protein intake also increased (g/day) from 45.6±14.2 at 3 months to 58.5±17.1 at 12 months (P=.04), and as a percentage of goal protein intake from 55.1%±23.0 at 3 months to 73.5%±38.0 at 12 months (P=.02). Although energy and protein intake increased significantly over the 12-month period, pro- tein intake at 12 months remained significantly lower (P=.01) than the daily recommended guidelines (1.5 g/kg IBW) for a low-energy restrictive diet. Energy intake did not differ in those who reported food intol- erances at 3 months (P=.77) or 6 months (P=.65), but was lower in them at 12 months (trend, P=.06). Also at 12 months, protein intake (P=.02) and percentage of protein intake goal (P=.04) were significantly lower in those with protein intolerance. Conclusions: These results suggest that postoper- ative patients consume insufficient amounts of pro- tein, possibly mediated by protein intolerance. Protein supplementation following RYGBP deserves further consideration. Key words: Protein intolerance, protein intake, morbid obesity, gastric bypass, bariatric surgery Introduction Although Roux-en-Y gastric bypass (RYGBP) is the most commonly performed bariatric surgical proce- dure in the United States, 1 little is known about the optimal postoperative nutritional management. Other than recommendations for vitamins, iron, and other mineral supplementation, there are no stan- dard recommendations for postoperative macronu- trient intake. RYGBP patients commonly consume <1000 kcal/d during the first year, 2 and their energy intake closely resembles a very low calorie diet, 500-800 kcal/day. 3 The small gastric pouch and the intestinal bypass limit energy and protein intake and absorp- tion. Reduced availability of pepsin, rennin, and hydrochloric acid from the bypassed distal stomach probably also limits protein digestion. In these patients, dietary intake is restricted at a time when protein requirements should be increased because of the catabolic response to surgery, especially during the early post-surgery period. The reduced protein intake may contribute to an excess loss of lean tis- sue. 4,5 Food intolerance and changes in food choices have also been reported in post-RYGBP patients, 6,7 as have alterations in taste perception for specific foods, 4,8 which may also contribute to inadequate protein intake. 2,7 The purpose of this study was to Obesity Surgery, 13, 23-28 © FD-Communications Inc. Obesity Surgery, 13, 2003 23 Obese Patients Have Inadequate Protein Intake Related to Protein Intolerance Up to 1 Year Following Roux-en-Y Gastric Bypass Violeta Moize, RD 1,2 ; Allan Geliebter, PhD 1 ; Marci E. Gluck, PhD 1 ; Eric Yahav, MA 1 ; Margarita Lorence, BS 1 ; Toni Colarusso, RD 2 ; Victoria Drake, RN 1 ; Louis Flancbaum, MD 1,2 New York Obesity Research Center, Departments of Medicine 1 and Surgery 2 , St. Luke’s/Roosevelt Hospital, Columbia University College of Physicians and Surgeons, NewYork, NY, USA and Unit of Obesity 2 , Hospital Clinico, Barcelona, Spain Reprint requests to: Violeta Moize Arcone, Registered Dietitian, Functional Unit of Obesity, Endocrinology and Nutrition Division, University Clinic Hospital, C/ Villarroel 170, 08039, Barcelona, Spain. Fax: +34 93 451 66 38; e-mail: violetamoize@yahoo.es