The Sleeve gastrectomy (also known as the Gastric Sleeve) procedure involves using staples to create a long tubular sleeve of stomach along the lesser curve side of the stomach with the remainder of the stomach, including most of the fundus & the body of the stomach, being removed permanently.
The new, long & thin ‘sleeve’ of a stomach is smaller than the original stomach, restricting the amount of food that it can hold, & so promoting weight loss.
The major effect of the procedure is to remove the part of the stomach that secretes Ghrelin, a hormone that plays a major role in determining how hungry we get. As people lose weight the stomach starts to produce an increased amount of Ghrelin that tells the brain to increase appetite. Patients who have had Gastric Sleeve surgery generally have a greatly reduced appetite & as they lose weight they do not suffer the hunger pains experienced by dieters.