BACKGROUND: Since 1984, biliopancreatic diversion (BPD) has been our procedure of choice in the treatment of morbid obesity. Better understanding of long-term outcome following BPD is needed. METHODS: We report the results of our first consecutive 92 patients who underwent BPD more than 5 years ago. Of these 92, only 82 were available for a recent formal evaluation after a mean of 79 months. RESULTS: Weight loss, was maintained over the years at 62% of initial excess weight; the success rate for losing more than 50% of initial excess weight was 72%. The gastrointestinal side-effects decreased with time, but diarrhea was still present in 13%. The average number of daily stools was 3 +/- 1.0. Of the patients, 76% were free from any gastrointestinal side-effects, taking normal diet and having normal stools. Malabsorption, however, was still present. A third of patients had laboratory values slightly below normal levels for hemoglobin, albumin and calcium. These values were mostly without clinical manifestation and were well tolerated by the patients. Regarding associated diseases, 75% were cured or improved following BPD. In 14 patients, reoperation was required to improve diarrhea or serum albumin. In these patients, the common channel was lengthened from 50 to 100 cm. The revision was successful in 11 and did not cause significant weight gain. CONCLUSIONS: BPD, as proposed by Scopinaro, was an efficient surgical treatment of morbid obesity that allowed normal eating habits and despite malabsorption was well tolerated by the great majority of patients.