How Much Is Gastric Bypass Surgery? Gastric bypass is the gastric bypass surgery for people with obesity problems, which helps the patient lose weight. The bypass can be defined as bridging or using shortcuts. Gastric Bypass means creating a passageway from the stomach to the intestines in general surgery. It is a method applied for various diseases that obstruct the stomach outlet. Gastric Bypass, in the sense used in obesity surgery, is a surgical method in which most of the stomach is disabled and the food taken is digested by using almost only half of the intestines.