Single-anastomosis duodenoileal bypass with sleeve gastrectomy/one anastomosis duodenal switch (SADI-S/OADS) was developed as a bariatric operation with reduced overall morbidity and lasting weight loss results. We performed a systematic review of the literature, including 14 studies reporting on weight loss, comorbidity resolution, postoperative complications, and nutritional deficiencies following SADI-S. Twelve months after SADI-S, the mean total body weight lost ranged from 21.5 to 41.2%, with no weight regain being observed after 24 months. The comorbidity resolution rate was 72.6% for diabetes, 77.2% for dyslipidemia, and 59.0% for hypertension cases. The need for reoperation was the most common postoperative complication. While several patients developed nutrient deficiencies, SADI-S seems to be an overall safe and effective bariatric operation.