This paper evaluates the biliopancreatic diversion with a duodenal switch (BPD-DS) procedure, a hybrid of restriction and malabsorption techniques. The study focuses on the first 440 patients who underwent this procedure without prior bariatric surgery, with an average starting weight of 183 kg and 41% of patients being super morbidly obese (BMI > 50). Key findings include an average maximum weight loss of 80% excess weight by 24 months post-operation, which continued at a 70% level for 8 years. Major complications occurred in nearly 9% of cases, including two perioperative deaths. All 36 type II diabetics discontinued medication after surgery, and 17 revisions were performed to address excess weight loss and low protein levels. The procedure was well-tolerated, with minimal weight regain, no marginal ulcers, no dumping syndrome, and no foreign material used. The authors conclude that this operation has significantly improved the lives of seriously obese patients with comorbidities, particularly type II diabetics, and is a functionally reversible procedure.This paper evaluates the biliopancreatic diversion with a duodenal switch (BPD-DS) procedure, a hybrid of restriction and malabsorption techniques. The study focuses on the first 440 patients who underwent this procedure without prior bariatric surgery, with an average starting weight of 183 kg and 41% of patients being super morbidly obese (BMI > 50). Key findings include an average maximum weight loss of 80% excess weight by 24 months post-operation, which continued at a 70% level for 8 years. Major complications occurred in nearly 9% of cases, including two perioperative deaths. All 36 type II diabetics discontinued medication after surgery, and 17 revisions were performed to address excess weight loss and low protein levels. The procedure was well-tolerated, with minimal weight regain, no marginal ulcers, no dumping syndrome, and no foreign material used. The authors conclude that this operation has significantly improved the lives of seriously obese patients with comorbidities, particularly type II diabetics, and is a functionally reversible procedure.