An inventive method for performing gastric bypass surgery and a gastric bypass band that is used in conjunction with the surgical method is disclosed. The inventive method involves separating a top portion of the stomach along with the esophagus from the remainder of the stomach, and re-connecting the separated portion to the small intestine to form a gastric pouch of about 20-30 cc in size. The inventive gastric band is placed midway along the gastric pouch to act as a restrictor valve to limit the amount of food passing through the valve. The band also retains food within the gastric pouch to give the patient a feeling of satiety. The band is comprised of an expansion-resistant section combined with a one-way latch mechanism. The latch has a curved orientation so that the band is formed into a radial profile when placed around the gastric pouch.