Gastric Sleeve / Vertical Sleeve Gastrectomy – VSG historically had been performed as the first stage of another bariatric procedure. However, some patients who undergo a VSG can actually lose significant weight with VSG alone and avoid a second procedure. A VSG operation restricts food intake by removing a significant portion of the stomach and does not lead to decreased absorption of food. The procedure may also decrease production of a hormone called ghrelin. A decreased amount of ghrelin may reduce hunger more than other purely restrictive operations, such as gastric band.