Gastric bypass is surgery that helps you lose weight by changing how your stomach and small intestine handle the food you eat.
After the surgery, your stomach will be smaller. You will feel full with less food.
The food you eat will no longer go into some parts of your stomach and small intestine that break down food. Because of this, your body will not absorb all of the calories from the food you eat.
See also: Laparoscopic gastric banding
You will have general anesthesia before this surgery. You will be asleep and pain-free.
There are two steps during gastric bypass surgery:
Gastric bypass can be done in two ways. With open surgery, your surgeon will make a large surgical cut to open up your belly. Your surgeon will do the bypass by working on your stomach, small intestine, and other organs.
Another way to do this surgery is to use a tiny camera, called a laparoscope. This camera is placed in your belly. The surgery is called laparoscopy.
In this surgery:
Advantages of laparoscopy over open surgery include:
This surgery takes about 2 to 4 hours.
You will usually not have weight-loss surgery unless you cannot lose a large amount of weight and keep it off by dieting, changing your behavior, and exercising alone.
Gastric bypass surgery is not a "quick fix" for obesity. You must diet and exercise after surgery. You also need to know about the risks of surgery, and what your life will be like after the surgery.
Gastric bypass is major surgery and it has many risks. Some of these risks are very serious. You should discuss these with your surgeon. Risks for any surgery or anesthesia include:
There are a number of risks for any weight-loss surgery. There are also risks that are more likely after gastric bypass surgery.
Your surgeon will ask you to have tests and visits with other health care providers before you have this surgery.
If you are a smoker, you should stop smoking several weeks before surgery and not start smoking again after surgery. Smoking slows recovery and increases the risks of problems. Tell your doctor or nurse if you need help quitting.
Always tell your doctor or nurse:
During the week before your surgery:
Most people stay in the hospital for 3 to 5 days after surgery.
In the hospital:
You will be able to go home when:
Most people lose about 10 to 20 pounds a month in the first year after surgery. Weight loss will decrease over time. By sticking to your diet and exercise from the beginning, you will lose more weight.
You may lose half or more of your extra weight in the first 2 years. You will lose weight quickly after surgery if you are still on a liquid or pureed diet.
Losing enough weight after surgery can improve many medical conditions, including:
Weighing less should also make it much easier for you to move around and do your everyday activities.
To lose weight and avoid complications from the procedure, you will need to follow the exercise and eating guidelines that your doctor and dietitian have given you.
Bariatric surgery - gastric bypass; Roux-en-Y gastric bypass; Gastric bypass - Roux-en-Y
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Updated by: Joshua Kunin, MD, Consulting Colorectal Surgeon, Zichron Yaakov, Israel. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.
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