Understanding the procedure
SADI-S (Single Anastomosis Duodeno-Ileal bypass with Sleeve gastrectomy) is the most powerful bariatric procedure available. It produces the highest weight loss outcomes — and requires the most commitment from the patient after surgery. This page explains what it involves, who it's designed for, and what lifelong follow-up looks like.
SADI-S combines two mechanisms: a sleeve gastrectomy (removing ~75% of the stomach) with a single intestinal connection that bypasses a significant portion of the small bowel. Unlike Roux-en-Y bypass, SADI-S uses only one surgical connection (anastomosis) instead of two — which reduces complexity compared to traditional biliopancreatic diversion.
The result: calories are absorbed much less efficiently. Combined with the restriction from the sleeve, this produces the highest documented weight loss of any bariatric procedure — typically 80–90% of excess weight at 12 months.
The trade-off is significant: SADI-S patients have the highest nutritional supplementation needs and require the most rigorous lifelong monitoring. This is not a procedure to take lightly.
Your surgeon will assess your full medical picture. SADI-S is not appropriate for every patient, and recommending it when sleeve or bypass would suffice is not our practice.
SADI-S delivers the best numbers — with the highest demands on the patient.
The highest outcomes of any bariatric procedure. Results vary by starting BMI, adherence to protocol, and post-op nutrition.
Strongest metabolic response of any procedure. Many patients see improvement within days, before significant weight loss.
SADI-S has the highest malabsorption. Fat-soluble vitamins (A, D, E, K), B12, iron, calcium, and zinc must be monitored consistently. This is non-negotiable.
SADI-S patients who skip supplementation or don't maintain follow-up are at serious risk of nutritional deficiencies — including protein malnutrition, bone loss, and neurological complications. These are not hypothetical. They happen to patients who had excellent surgical outcomes but didn't maintain post-op care. We include a structured 12-month protocol because it's how we prevent this.
The classic biliopancreatic diversion with duodenal switch (BPD-DS) required two intestinal connections. SADI-S simplifies this to one, reducing operative time and complication risk while producing comparable outcomes. Most high-volume bariatric centers now prefer SADI-S over traditional DS for this reason.
Some patients who had sleeve gastrectomy years ago don't reach their weight loss goals, or regain significant weight. In many cases, converting the sleeve to SADI-S (adding the intestinal bypass component) produces additional significant weight loss. Revision surgery is more complex than primary surgery — recovery and monitoring requirements are higher.
Yes, after the full recovery period. SADI-S patients do need to be more attentive than sleeve patients to protein intake and fat consumption. Dietary fat triggers stronger GI symptoms (loose stools, odor) if consumed in excess — a common adjustment period in the first year. Most patients adapt their diet and report good quality of life long-term.
Our surgeons are conservative in recommending SADI-S. If it's the right tool for your situation, they'll tell you directly — and explain exactly why.