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Weight-Loss Surgery (Bariatric Surgery)


The Manual's Editorial Staff

Reviewed/Revised Oct 2023
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What is weight-loss surgery?

Weight-loss surgery is surgery to the stomach or intestine (or both) to help you lose weight. It's also called bariatric surgery.

To qualify for weight-loss surgery, you must:

  • Have tried other ways of losing weight

  • Be physically and mentally able to have surgery

  • Be ready to follow your doctors’ instructions after surgery about what to eat, how much to exercise, and when to get follow-up tests

How do doctors do weight-loss surgery?

Your stomach is where food first goes when you swallow it. The stomach starts digesting food and then passes it into the intestines. The intestines finish digesting food and take the nutrients into your body. Weight-loss surgery does one or both of the following:

  • Makes your stomach smaller to limit the amount of food you can eat

  • Bypasses part of your intestines so less food can be absorbed

The most common weight-loss surgeries include:

Gastric bypass is the most common type of surgery. After this surgery, your stomach can hold only a small amount of food. Food that leaves the stomach bypasses the first part of the small intestine.

Your doctor will recommend the type of weight-loss surgery best for you.

Doctors can do some weight-loss surgery with laparoscopy. Instead of cutting your belly open, doctors put a viewing tube (laparoscope) and surgical tools in through small cuts in your belly. Laparoscopy is generally safer and you recover quicker than with regular (open) surgery.

Bypassing Part of the Digestive Tract

In gastric bypass, part of the stomach is detached from the rest, creating a small pouch. The pouch is connected to a lower part of the small intestine.

Bypassing Part of the Digestive Tract

Banding the Stomach

In adjustable gastric banding, an adjustable band is placed around the upper part of the stomach. It enables doctors to adjust the size of the passageway for food through the stomach as needed.

Banding the Stomach

How should I eat after weight-loss surgery?

You may have to wait about 4 weeks to eat solid food. For the first 2 weeks, you'll drink protein drinks. For the next 2 weeks, you may start eating some soft, mushy, or pureed foods.

When you start eating solid foods, your doctor may recommend:

  • Taking small bites of food

  • Chewing food carefully

  • Not eating high-fat and high-sugar foods, such as fast food, cakes, and cookies

  • Eating only small meals

  • Not drinking liquids when eating solid foods

Even though having a smaller stomach makes it easier to eat less, some people still eat too much. Some people drink lots of shakes or other high-calorie liquids. Others keep eating even when they're full and gradually stretch out their smaller stomach. Even though you had surgery, you still have to watch what you eat so you lose weight and don't gain it back.

Also, because you aren't absorbing food normally, you have to be careful you get enough vitamins, minerals, proteins, and other important nutrition.

Changing how you eat can be hard. Counseling or a support group may help.

What are the benefits of weight-loss surgery?

How safe is weight-loss surgery?

All surgeries have a chance of:

  • Infections near the site of surgery

  • Blood clots in your lungs

  • Lung infection (pneumonia)

Weight-loss surgeries also have a small chance of:

Because of these risks, doctors do weight-loss surgery only for people who have severe obesity Obesity Obesity is having too much body fat. Obesity causes health problems. The fatter you are, the higher your risk of health problems. Obesity is caused by eating more calories than your body needs... read more or who are very overweight and have a serious weight-related health problem. Talk to your doctors about the risks of surgery.

Call your doctor right away if you have signs of infection around your wound, such as:

  • Redness

  • Severe pain

  • Swelling

  • Bad smell

  • Oozing

Call your doctor right away if you have these warning signs after surgery:

  • Severe belly pain

  • Fever or chills

  • Throwing up

  • Bleeding

  • Fast or skipping heartbeats

  • Diarrhea

  • Dark, tarry, bad-smelling stools

  • Shortness of breath

  • Sweating

  • Sudden paleness

  • Chest pain

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