SADI-S Surgery in Bangkok, Thailand

Key takeaways

• SADI-S is a sleeve gastrectomy plus a single bowel connection; it is a simplified form of the duodenal switch and keeps the valve at the stomach outlet (the pylorus).
• It is usually considered at a higher BMI, with type 2 diabetes, or when weight has returned after a sleeve gastrectomy.
• In a French randomised trial of 381 patients (SADISLEEVE, The Lancet, 2025), SADI-S led to more excess weight loss than gastric bypass at 2 years, with a similar number of serious adverse events.
• Fewer nutrients are absorbed, so lifelong supplements, protein targets and regular blood tests are part of the treatment. SADI-S is priced in a written quotation after assessment.

Who SADI-S may suit

• Type 2 diabetes, especially when it has been difficult to control.
• Weight that has returned after a sleeve gastrectomy. The existing sleeve is kept and the bypass is added. How this compares with other surgical options is explained on revision after sleeve gastrectomy.
• People who can commit to lifelong supplements, blood tests and follow-up.

What the evidence shows

SADI-S was introduced in 2007, so it has less long-term data than a sleeve or a gastric bypass.

• Professional societies. ASMBS endorsed SADI-S in 2020 as an appropriate metabolic and bariatric operation, advising a cautious approach until long-term data are published (Kallies and Rogers, Surgery for Obesity and Related Diseases, 2020). IFSO, the International Federation for the Surgery of Obesity and Metabolic Disorders, endorsed it in 2021. Its 2023 update reviewed 93 studies and found effective weight loss and medium-to-long-term control of type 2 diabetes, but frequent deficiencies of fat-soluble vitamins, anaemia and low albumin (a blood protein). It noted that high-quality evidence remains scarce and recommended lifelong supplements and monitoring (Obesity Surgery, 2024).
• A randomised trial against gastric bypass. SADISLEEVE (Robert and colleagues, The Lancet, 2025) allocated 381 patients at 22 French centres, mean BMI 46.2, to SADI-S or gastric bypass. At 2 years, excess weight loss averaged 76.0% after SADI-S and 68.1% after gastric bypass. Serious adverse events related to the operation numbered 40 after SADI-S, including three leaks at the bowel connection and eight cases of severe diarrhoea, and 35 after gastric bypass. Results were missing for 20% of patients at 2 years.
• About 10 years of follow-up. Sánchez-Pernaute and colleagues (Obesity Surgery, 2022) followed 164 patients. Total weight loss was 38% at 5 years and 34% at 10 years. Of 41 patients with diabetes who used insulin before surgery, 7 still did at 5 years and 12 at 10 years. Twelve patients needed further surgery because of low protein levels.
• Compared with the classic duodenal switch. A two-centre study (El Ghazal and colleagues, Surgical Endoscopy, 2025) of 32 patients after SADI-S and 101 after duodenal switch found similar maximum total weight loss (47.3% and 45.7%), with fewer nutritional complications after SADI-S (15.6% and 53.5%).

Excess weight loss is the share of weight above a healthy reference weight that is lost; total weight loss is the share of your starting weight. These are published averages, not a prediction for you.

Planning your trip from abroad

1. Send your details on WhatsApp: height, weight, health conditions, medicines and any previous surgery.
2. Video consultation with a member of the clinic's bariatric surgical team, comparing SADI-S with a sleeve or a gastric bypass for you.
3. Written quotation for your plan, before any deposit.
4. Follow-up from home, with supplements, blood tests and dietitian support.