Sleeve gastrectomy vs. Roux-en-Y gastric bypass

Mechanism

Sleeve gastrectomy is primarily restrictive with hormonal effects. Roux-en-Y combines restriction, malabsorption, and neurohormonal effects by rerouting a portion of the small intestine.

Weight outcomes

Both procedures produce substantial average weight loss in published cohorts. Long-term randomized data (e.g. SLEEVEPASS, SM-BOSS) show durable results with both, with some differences by patient population and follow-up length.

Type 2 diabetes

Both procedures can improve or induce remission of type 2 diabetes; Roux-en-Y has a longer evidence base for metabolic effect, and comparative trials (e.g. STAMPEDE) support significant improvement with both surgical approaches.

Reflux (GERD)

Sleeve gastrectomy can worsen reflux in a subset of patients; Roux-en-Y typically improves reflux and is often preferred when severe reflux is present.

Nutritional considerations

Roux-en-Y has a higher risk of specific deficiencies (iron, B12, calcium, vitamin D) and requires more intensive lifelong supplementation than sleeve.