Restrictive gastric operations, such as an adjustable gastric banding procedure, serve only to restrict and decrease food intake and do not interfere with the normal digestive process.In this procedure, a hollow band made of special material is placed around the stomach near its upper end, creating the small pouch and a narrow passage into the larger remaining portion of the stomach. This small passage delays the emptying of food from the pouch and causes a feeling of fullness.The band can be tightened or loosened over time to change the size of the passage. Initially, the pouch holds about 1 ounce of food and later expands to 2-3 ounces.