The aim of this study was to determine prospectively the efficacy and safety of the biliopancreatic diversion with Roux-en-Y gastric bypass (BPD with RYGBP) procedure used as the primary bariatric procedure in super obese patients. The main characteristics of the BPD with RYGBP procedure were a gastric pouch of 15 +/- 5 ml, biliopancreatic limb of 200 cm, common limb of 100 cm, and alimentary limb of the remainder of the small intestine. From June 1994 through July 2003, 132 super obese patients (body mass index [BMI]: 57 +/- 7), with an incidence of comorbidities 6 +/- 2 per patient, underwent BPD with RYGBP and subsequent follow-up. Mean follow-up time was 29 +/- 14 months. Maximum weight loss was achieved at 18 months postoperative with average excess weight loss (EWL) 65%, average initial weight loss (IWL) 39%, and average BMI 35 kg/m(2). Thereafter, a decline was observed with EWL stabilizing at around 50%, IWL at around 30%, and BMI at around 40 kg/m(2), respectively, by the end of the study period. The majority of preexisting comorbidities were permanently resolved by the 6-month follow-up visit. Early mortality was 1% and early morbidity was 11%. Late morbidity was 27%, half of which was due to incisional hernia. Deficiencies of microelements were mild and successfully treated with additional oral supplementation. The incidence of hypoalbuminemia was 3% and there were no hepatic complications. We conclude that BPD with RYGBP is a safe and effective procedure for the super obese with few metabolic complications.