The main difference between the standard roux-en-y gastric bypass (RYGB) and the MGB is that there is only one join or anastomosis. In contrast, in the RYGB, there are two – an upper and a lower. Because of this, the MGB can be done in less time than the RYGB and – at least theoretically – with fewer early complications.

The stomach is divided in the first part of mini gastric bypass surgery. First, a small stomach tube is created, which becomes the pouch. This is the restrictive part of the procedure and means that only a tiny amount of food can be taken at any one time. Next, a Doral surgeon brings up a loop of the bowel (about 200-300cm long) and joins this to the lower part of the stomach pouch. This means that food passes from the small pouch into the small bowel, where it meets the digestive juices, which have moved downwards from the main part of the stomach. In effect, therefore, about 2-3 meters of the small bowel have been bypassed before absorption of food (and calories). Fewer calories absorbed means weight loss.