Gastric bypass using the Roux-en-Y procedure is a combination procedure. First, the surgeon sections off a small portion of the stomach to create a new stomach pouch. Then he sections off a portion of the small intestine and attaches it to the new stomach pouch using surgical staples. The smaller size of the stomach allows you to feel fuller sooner and eat less food (restriction). Since calories are absorbed in the small intestine, bypassing a lengthy portion of it means your body absorbs fewer calories (malabsorption).
