It turns out, as shown in a recent study, that a procedure known as the "duodenal switch" is better than gastric bypass in achieving weight loss in patients who are very obese, (those with a Body Mass Index of at least 50). Roux-en-Y gastric bypass is known to be an effective weight-loss operation for patients with a BMI between 35 and 50. For super-obese patients, however, this operation is...