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Bariatric Surgery

Sleeve Gastrectomy

How is a sleeve gastrectomy done?


A sleeve gastrectomy is a surgery that removes most of the stomach (about 80%). To do a sleeve gastrectomy, a surgeon uses surgical staples to divide the stomach into two parts. The long and narrow part of the stomach that stays in the body is called a sleeve. The rest of the stomach is removed from the body.

How does a sleeve gastrectomy help you lose weight?

When you eat, food passes into the sleeve from the throat and to the intestines. After the surgery, your stomach is much smaller ‒ about 1/3 to 1/2 cup (80 to 125 ml) in size. You’ll only be able to eat about 1 cup (250 mL) of food at a time so you’ll feel full even when you eat smaller portions. Eating less food often means taking in fewer calories, which will help you lose weight.

After surgery, your body will make less ghrelin (a hormone that makes you feel hungry). When your body makes less ghrelin, you won’t feel as hungry.

Your body will be able to absorb most nutrients from the food you eat. This is because food will still pass through the lower part of the stomach to the upper part of the small intestine, where most foods are absorbed. But you’ll still need to take vitamins and minerals to get all the nutrients you need.

What are the risks or side effects of a sleeve gastrectomy?

The following are some of the risks and side effects of having a sleeve gastrectomy.

The surgery can’t be reversed

When you have a gastric sleeve, you won’t be able to have surgery to make the stomach full size again (have the surgery reversed) because most of the stomach was removed.

Some people may have another surgery to change to a gastric bypass.

Not getting enough vitamins and minerals

You are at risk for low levels of vitamins and minerals because you are eating less food and your body doesn’t absorb as many nutrients after surgery.

To help your body get enough vitamins and minerals after surgery:

  • eat healthy meals and snacks
  • take vitamin and mineral supplements each day

You should also go for regular blood tests to check your vitamin and mineral levels. This will help your health care provider know how many extra vitamins and minerals ​your body needs.

Weight gain

After surgery you will eat smaller portions. You may gain weight back if you take in extra calories by:

  • choosing high calorie foods more often
  • eating too much or eating too often (called grazing)

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