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Bariatric care: Roux-en-Y gastric bypass surgery

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This surgical weight loss option is available at...

To start your weight loss surgery journey, attend a free surgery information class.

Losing weight can be difficult. Gastric bypass surgery, which reduces the size of your stomach, and changes the route of your intestines, is a way to limit the amount of food you eat. Although this may sound like an easy answer, it is not magic.

This surgery requires lifelong changes in your eating habits and your attitude about food. Every day you will need to make good food and exercise choices.

For a healthy lifestyle after surgery, you will need to make behavior as well as nutrition changes. Thousands of patients have succeeded with this program. With your full commitment and the support of family and friends, you can too. You will also get support from your bariatric surgery team. They will provide information, help, encouragement and guidance.

In general, patients lose:

  • 66 to 69 percent of their excess weight at one year post-operation
  • 63 to 65 percent of their excess weight at three years post-operation

What's gastric bypass surgery?

Roux-en-Y gastric bypass surgery changes the size of your stomach as well as your ability to absorb calories to help you succeed at long-term weight loss.

  • Your surgeon will reduce the size of your stomach with this surgery. Your stomach will be stapled and then divided, making two different sections: the new stomach or pouch, and the bypassed stomach.
  • Part of your small intestine will be separated and attached to the pouch so your food will go right into the small intestine after it goes through the pouch. You will absorb fewer calories because of this.
  • The bypassed stomach is sewn closed, but will continue to produce acid and digestive juices that drain into your digestive tract. Because the small intestine is separated and part of it is attached to your new pouch, it will look like a "Y" and that's where the surgery got the "Y" in its name.

This surgery cuts down the amount of food and liquid you can hold at one time. Your pouch will hold about one to two tablespoons of food at the beginning.

As you fill this pouch, a signal is sent to your brain that you feel "satisfied" and should stop eating. If you try to eat too much or too quickly, you may feel a wave of nausea or abdominal pain, or you may vomit.

Are there risks to gastric bypass surgery?

This surgery does carry risks. Possible complications include infection, bleeding, anesthesia risks, hernia, leaks, blood clots and ulcers. Also, the outlet at the bottom of your pouch may get plugged (clogging), or your body might not absorb some vitamin and minerals you need. Death from weight loss surgery is a risk but it is not common. This is about the same as that for gallbladder surgery or a hip replacement.

Please discuss potential risks with your surgeon.

arrow points to link to page about eating after weight loss surgeryRead about possible problems after gastric bypass surgery.

What happens during recovery?

You will need to commit to a lifestyle of healthful eating and regular exercise for the rest of your life. This will help you avoid re-gaining weight and help you manage your health.


Source: Allina Health's Patient Education Department, Roux-en-Y Gastric Bypass Surgery: What You Need to Know Before and After Surgery, fourth edition, surg-ahc-90091
Reviewed by: Allina Health's Patient Education Department
First Published: 01/21/2005
Last Reviewed: 02/15/2010