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What is weight-loss surgery?
Weight loss surgery helps people lose weight. There are two types of surgeries. They can be restrictive or a combination of restrictive and malabsorptive.
- Restrictive: This type of surgery makes the stomach smaller. It limits the amount of food the stomach can hold.
- Malabsorptive: This surgery changes the path of the intestine. Food goes around (or bypasses) part of the intestine. Since nutrients are normally absorbed in the intestine, bypassing a part of it reduces how much it can absorb. This can lead to weight loss.
Weight-loss surgery is usually only done if your body mas index (BMI) is at least 40. Surgery may also be an option if your BMI is at least 35 and you have other health problems related to your weight. With a BMI of at least 35 or higher, surgery may be done if you have tried for at least 6 months to lose weight with diet and exercise.
Weight-loss surgery is also called bariatric surgery. The three main types are:
- Adjustable gastric banding: The doctor wraps a band around the upper part of the stomach. Attached to the band is a thin tube leading to an access port that is left under the skin. About 4 to 6 weeks after surgery, the doctor puts a needle in the access port to add or take away salt water (saline) in the band. Adding saline tightens the band and makes the stomach smaller. The doctor can take away saline if the band is too tight.
- Gastric sleeve: The doctor removes more than half of your stomach, leaving a thin vertical sleeve, or tube, that is about the size of a banana. Because part of your stomach has been removed, this surgery is not reversible.
- Gastric bypass: The doctor uses a small part of your stomach to create a smaller stomach. The new stomach is connected to the middle part of the small intestine. Food skips (bypasses) the rest of the stomach and the upper part of the small intestine. Bypassing part of the small intestine reduces how much food, nutrients, and calories are used by the body. This can cause weight loss. This type of gastric bypass surgery is called a Roux-en-Y (say "roo-en-why") gastric bypass.
How is this surgery done?
Weight-loss surgery is done in one of two ways.
- Open surgery. The surgeon makes a large cut in the belly.
- Laparoscopic surgery. The doctor makes several small cuts and uses small tools and a camera to guide the surgery. You recover sooner from this type of surgery. And you are less likely to have pain or problems after surgery.
What's usually involved?
Having weight-loss surgery is a big step. After surgery, you'll need to make new, lifelong changes in how you eat and drink.
You'll work with a team that's trained to help you lose weight and make healthy changes in your life. They will be there to help you prepare for surgery. Before your surgery, ask your team how they will help you prepare for life after surgery while you adjust to new ways of eating and changes to your body.
Your team may include:
- A medical doctor or nurse to help manage your care and schedule tests before surgery.
- A surgeon who specializes in weight-loss surgery.
- A registered dietitian to help you plan meals and make changes in the way you eat.
- An exercise specialist to help you be more active and get stronger.
- A therapist or counselor to help you learn why you eat too much and teach you ways to deal with stress and your emotions.
How well does weight-loss surgery work?
Depending on the type of surgery, most people lose at least a third of their extra weight after surgery. Some people lose almost all of their extra weight. Weight loss varies with the type of surgery. It also depends on how closely people follow their doctor's recommendations for lifestyle changes, check-up appointments, and counseling.
In a study comparing banding and gastric bypass, banding had fewer surgical risks than gastric bypass. But people who got gastric banding tended to lose less weight. They also lost weight more slowly than those who had gastric bypass.
People who had gastric sleeve surgery or gastric bypass tended to lose the most weight. Gastric sleeve surgery is less effective than gastric bypass, but it has fewer risks.
What are the risks of weight-loss surgeries?
People who are very overweight are more likely than other people to have problems from any kind of surgery. And after any weight-loss surgery:
- You could get an infection in the area where cuts were made.
- A blood clot can form and block blood flow in the lung (pulmonary embolism).
- You may not get enough of certain vitamins and minerals. This can lead to problems such as anemia and osteoporosis.
- Some people get gallstones.
- You may gain the weight back a few years after surgery if you don't follow your eating and lifestyle plan.
What are some of the risks of each type of surgery?
Talk to your doctor to understand all of your risks. Here are some of the most common or serious risks for each of the weight-loss surgeries.
- After adjustable gastric banding, you are more likely to need another surgery to fix problems than you would after gastric bypass. For example, some people need a second operation because they aren't happy with having the band. Or the band can slip, or it can work its way from the outside of the stomach to the inside. This is called an erosion.
- Gastric bypass and gastric sleeve surgeries can cause a leak from the stomach into the belly area. The leak can cause an infection called peritonitis.
- With gastric bypass, the connection between the stomach and the small intestine can get narrow. This can cause nausea and vomiting after eating.
Remember that weight-loss surgery is not cosmetic surgery. It will not remove fatty tissue. And after a lot of weight loss, you may have excess skin. Some people choose to have more surgery to remove skin from the belly, thighs, upper arms, or breasts.
Current as of: September 23, 2020
Author: Healthwise Staff
Kathleen Romito MD - Family Medicine
Martin J. Gabica MD - Family Medicine
David E. Arterburn MD, MPH - Internal Medicine
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