• Skip to primary navigation
  • Skip to main content
  • Skip to footer
BOMSS

BOMSS

British Obesity & Metabolic Surgery Society

  • Home
  • About BOMSS
    • About BOMSS
      • Overview
      • Vision, mission and values
      • Equality, diversity and inclusion
    • Who we are
      • Trustees
      • Council
      • Patient Safety Committee
      • Endoscopy Committee
      • IHP Committee
      • NBSR
    • Membership
  • Healthcare Professionals
    • Clinical Resources
    • BOMSS GP Hub
  • Annual Scientific Meeting
    • Annual Scientific Meeting 2025
    • Annual Scientific Meeting 2024
    • Annual Scientific Meeting 2023
    • Annual Scientific Meeting 2022
    • Annual Scientific Meeting 2021
  • Events
  • Patient information
  • Contact
  • About
        • Overview
        • Who we are
          • Council
          • Trustees
          • Patient Safety Committee
          • Endoscopy Committee
          • IHP Committee
          • NBSR
        • Membership
        • Equality, diversity and inclusion
        • Vision, mission and values
        • Contact
  • Patient information
    • What is obesity?
    • How is obesity measured?
    • Obesity-linked health problems
    • Managing obesity
      • Your mindset
      • Medication
      • NHS Tiered Care Weight Management Pathway
      • Bariatric and Metabolic Surgery
        • Adjustable Gastric Banding
        • Gastric Bypass – Roux en Y Gastric Bypass
        • Sleeve Gastrectomy
        • One-anastomosis (Mini) Gastric Bypass (OAGB)
        • Bilio-Pancreatic Diversion With Duodenal Switch (BPD-DS)
        • Bariatric surgery for people with type 2 diabetes (T2D)
    • Accessing Tier 4 Services
  • ASM
    • ASM 2025
    • ASM 2024
    • ASM 2023
    • ASM 2022
    • ASM 2021
    • Event calendar
  • Healthcare professionals
    • Clinical Resources
    • BOMSS GP Hub

Gastric Bypass – Roux en Y Gastric Bypass

You are here: Home / Patient information / Managing obesity / Bariatric and Metabolic Surgery / Gastric Bypass – Roux en Y Gastric Bypass

Gastric bypass has been performed as a treatment for severe obesity since 1960’s. The surgery involves stapling across the stomach to create a small pouch (size of an egg), the ‘new’ stomach. The rest of the stomach remains inside you, but food does not go into this. The small intestine is re-plumbed creating a short cut from the new stomach to the mid-part of the small intestine, bypassing the first part of the small intestine.

Gastric bypass works by several mechanisms. Most importantly, the rerouting of the food stream alters gut signals leading to increased satiety, reduced hunger, changes in taste and improved blood sugar. In addition, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed.

On average, people lose 20-30% of their total body weight.

Gastric bypass requires adherence to dietary recommendations, lifelong vitamin/mineral supplementation, and follow-up compliance. The surgery can be reversed if required.

Smoking significantly increases risks associated with this operation.

Surgical options:

  • Adjustable Gastric Banding
  • Gastric Bypass
  • Sleeve Gastrectomy
  • One-anastomosis Gastric Bypass
  • Bilio-Pancreatic Diversion With Duodenal Switch
  • Bariatric surgery for people with type 2 diabetes

Footer

Quick links

  • Home
  • About
  • ASM
  • Events
  • Contact
  • Privacy policy

Contact

British Obesity & Metabolic Surgery Society CIO (BOMSS)
C/O Executive Business Support
Davidson Road
City Wharf
Lichfield
WS14 9DZ

info@bomss.org

01543 442 195

Copyright © 2025 British Obesity & Metabolic Surgery Society CIO    I

I   Registered charity No: 1192184