The gastric bypass is a more complicated procedure and involves the creation of a small pouch at the top of the stomach with staples. The remaining stomach stays in place. A section of intestine is ‘plumbed’ into this pouch so that the food bypasses the rest of the stomach and enters the intestine lower down. There are therefore two joins of the intestine inside. It works by limiting the amount you can eat at each mealtime but also by altering the hormone levels produced by the gut to improve diabetes and make you less hungry. The operation takes about one hour and the hospital stay is usually 1 day.
Advantages: It is very effective at weight loss and may be the best option in diabetes and acid reflux.
Disadvantages: The risks of surgery are higher than for simpler operations, it is essentially irreversible and you will need to take daily vitamin supplements for life after surgery.