The initial era of bariatric surgery began with the observation that a surgically shortened small intestine and secondary malabsorption resulted in sustained weight loss. In 1954, Kremen et al.

When was the first bariatric surgery performed?

The first weight-loss surgery performed was a Gastric Bypass surgery in 1954 by Dr. A.J. Kremen. Kremen and his team connected the patient's upper and lower intestine, which bypassed a large amount of where the calories are absorbed.

How long has gastric bypass surgery been around?

The first operations designed solely for the purpose of weight loss were initially performed in the 1950s at the University of Minnesota. The jejunoileal bypass (JIB) induced a state of malabsorption by bypassing most of the intestines while keeping the stomach intact.