SADI-S (single anastomosis duodeno–ileal bypass with sleeve gastrectomy) is a bariatric surgical technique to address metabolic disorders and to lose weight.

It is a variation on the duodenal switch surgery, incorporating a vertical sleeve gastrectomy with a gastric bypass technique.

In published studies,[2] total weight loss and the positive impact or remission of type 2 diabetes was better with the SADI-S surgery than with gastric bypass or sleeve gastrectomy.

When compared to RNY surgery, the SADI preserves the stomach/pyloric valve, thus maintaining more anatomical control over release of food into the intestines, and reducing the risk or frequency of dumping syndrome.

As with other bariatric malabsorptive techniques, including RNY and DS, patients will need to take vitamin supplements A, D, E, K and minerals throughout their lives.