The Roux-en-Y Gastric Bypass combines restrictive and malabsorptive procedures and comprises 75 percent of bariatric surgical procedures.

• During the procedure, stapling is used to create a small, upper-stomach pouch that restricts the amount of food able to be consumed.
• A portion of small intestine is bypassed and connects the new stomach pouch with the remainder of the small intestine.
• This bypassed limb delays food from mixing with digestive juices to avoid complete caloric absorption.
• The malabsorption obtained after the gastric bypass is not to the extent as after true malabsorption operations (biliopancreatic bypass/duodenal switch).
• Weight loss is achieved by drastically limiting the amount of food or liquids that a patient can ingest.