Sleeve gastrectomy is a restrictive form of weight loss surgery in which approximately 85% of the stomach is removed leaving a cylindrical or sleeve shaped stomach with a capacity ranging from about 60 to 150 cc, depending upon the surgeon performing the procedure. Unlike many other forms of bariatric surgery, the outlet valve and the nerves to the stomach remain intact and, while the stomach is drastically reduced in size, its function is preserved.

Again, unlike other forms of surgery such as the Roux en Y gastric bypass, the sleeve gastrectomy is not reversible.