WebMD Logo Icon
WebMD Connect to Care helps you find services to manage your health. When you purchase any of these services, WebMD may receive a fee. WebMD does not endorse any product, service or treatment referred to on this page. X

What is Bariatric Surgery?

Bariatric surgery provides an alternative option for weight loss for patients who meet the appropriate medical criteria, and for whom diet and exercise have proven ineffective.

Bariatric surgery is a term that refers to surgical procedures that assist in weight loss by making changes to the digestive system. The term "bariatric surgery"can be used to describe a variety of procedures, such as gastric bypass and other weight loss surgeries.

While different types of bariatric surgeries work differently, they are all very serious procedures.

Types of bariatric surgery

Bariatric surgeries work in different ways, whether by restricting the amount of food a stomach can hold, reducing the body’s ability to absorb nutrients, or a combination of the two. The most common types of bariatric surgery include gastric bypass, sleeve gastrectomy, adjustable gastric band, and duodenal switch.

Gastric bypass: Gastric bypass surgery is one of the most common types of bariatric surgery. Simply put, there are two parts to the procedure. First, a small pouch is created in the top portion of the stomach, dividing it from the rest of the stomach. Then the first part of the small intestine is divided, and the bottom end of the small intestine is connected to the newly created small pouch in the stomach. Finally, the top portion of the divided small intestine is connected to the bottom of the small intestine, which changes the food stream and produces changes in gut hormones. This procedure both limits the amount of food the stomach can hold, as well as restricts absorption of calories and nutrients.

Sleeve gastrectomy: Involves the removal of approximately 80% of the stomach. What is left is a tube-shaped pouch, or a sleeve. Now that the stomach is smaller, it cannot hold as much food. It also reduces the production of the hormone ghrelin, which regulates the appetite.

Gastric band: The adjustable gastric band involves placing an inflatable band around the top portion of the stomach, which creates a smaller pouch above. Less food is able to be stored and patients achieve fullness faster. The band is reduced in size over time with repeated adjustments.

Duodenal switch: The Biliopancreatic Diversion with Duodenal Switch (BPD/DS) has two parts to it, as well. First a portion of the stomach is created to form a tube-shaped pouch (similar to sleeve gastrectomy). Second, a major portion of the small intestine is bypassed. What this does is restricts the amount of food the stomach can hold and promotes fullness faster. It also reduces the absorption of nutrients. It is a highly effective surgery, but it also involves greater risk, such as vitamin deficiencies or malnutrition.

Why is bariatric surgery done?

Bariatric surgery is performed to help patients who are severely overweight lose excess weight in order to lower the risk of severe, life-threatening health problems, such as:

  • Heart disease
  • Stroke
  • High blood pressure
  • Nonalcoholic fatty liver disease
  • Sleep apnea
  • Type 2 diabetes

Keep in mind that bariatric surgery is not for everyone who is overweight. Certain medical criteria need to be met. It is typically suggested after other methods of weight loss, like changing diet and exercise, are unsuccessful.