Gastric bypass

The basics

  • A small stomach pouch about the size of a golf ball is created.
  • The new, smaller stomach pouch is connected directly to the middle portion of the small intestine, called the jejunum.
  • The rest of the stomach and the upper portion of small intestine, called the duodenum, is bypassed.

How it works

  • Restricts how much you can eat at one time.
  • Makes you feel full with less food.
  • Not all energy or calories from food are absorbed or used in the body.


  • Average weight loss is 55–60% of excess body weight* long-term. 
  • Improves diabetes management.
  • Improves heartburn.


  • Risks include, but are not limited to:
  • Ulcer
  • Scarring
  • Bowel obstruction
  • Low vitamin levels (deficiencies)
  • Death

*“Excess body weight” means how many pounds you weigh over your ideal body weight. For example, if you are 100 pounds overweight, you could expect to lose on average 55–60 pounds.

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