Gastric bypass surgery is the most popular bariatric surgery in the United States. It has been used since 1968 to help control obesity through both restrictive and malabsorptive ways. The surgery is now typically done as a laparoscopic procedure and involves a lower chance of complications due to an open surgery procedure.
Having been around the longest, gastric bypass is the most studied with the most outcomes to review. It has been the most successful in both the amount of weight lost as well as resolving health issues such as Type 2 Diabetes, hyperlipidemia, hypertension, sleep apnea and back pain.
In this procedure, the surgeon creates a small stomach pouch and then constructs a "bypass" for food. The bypass allows food to skip parts of the small intestine. By skipping a large part of the small intestine, the body cannot absorb as many calories or nutrients.
This procedure is permanent and nonreversible.