Overview of the Gastric Sleeve Procedure

Gastric Sleeve Surgery is one of the newest types of weight loss surgery to be used in the treatment of severe obesity. The relative safety and numerous advantages of gastric sleeve surgery compared to other bariatric procedures has made it an increasingly popular option with both bariatric surgeons and patients seeking surgical treatment for obesity.

The procedure is a restrictive type of weight loss surgery that surgically reduces the size of the stomach to limit food intake and lessen the sensation of hunger. The procedure does not involve cutting, rerouting, or bypassing any portion of the small intestine like gastric bypass, nor does it require a medical implant or periodic adjustments as with gastric banding.

Gastric Sleeve

Approach to Weight Loss

The gastric sleeve procedure, also known as Sleeve Gastrectomy, Gastric Sleeve Resection or Vertical Sleeve Gastrectomy (VSG), promotes weight loss by restricting food intake (a restrictive bariatric procedure) rather than altering food absorption (a malabsorptive bariatric procedure).

During surgery, the bariatric surgeon sections off approximately 60 to 80% of the stomach along the greater curvature. The cutaway part of the stomach is removed from the body, leaving a new stomach pouch that resembles a narrow tube, or "sleeve," that extends from the natural stomach opening to the natural stomach outlet (pyloric valve). The stomach reduction is permanent and the gastric sleeve procedure is not reversible.

The procedure limits eating by reducing the overall size of the stomach and controls hunger by removing the part of the stomach that produces the hunger-stimulating hormone Ghrelin. It induces weight loss by helping patients eat less and feel full faster on a smaller amount of food.

In studies to date, the gastric sleeve surgery has been shown to be a safe and effective alternative to the other common options of gastric bypass and gastric banding. The operation encompasses many of the benefits of these two procedures with few of the disadvantages.

More information about restrictive weight loss procedures can be found in our side-by-side comparison chart that compares gastric sleeve to gastric banding weight loss surgery.

Although the gastric sleeve procedure has been gaining attention in recent years, it is not a completely new type of surgery for weight loss. It has been performed by bariatric surgeons for quite some time, but usually as the first part of a two-stage operation. Originally, the gastric sleeve surgery was designed to be followed up by a second procedure, either gastric bypass or duodenal switch surgery, at a later date. The purpose of the two-stage approach is to make weight loss surgery safer for high-risk patients, particularly individuals with a high body mass index (BMI greater than 50 to 60) and/or with health conditions that make them unacceptable candidates for a single, combined restrictive and malabsorptive surgery.

It has only been in recent years that bariatric surgeons have begun to perform gastric sleeve surgery as a stand-alone weight loss procedure. With this new approach, the stomach pouch is usually made smaller than in duodenal switch patients. While long term results are not yet available, short term weight loss results have been primarily favorable, especially in low BMI patients (BMI 35 to 45).


  • Promotes weight loss by restricting amount of food that can be eaten at any one time
  • Reduces hunger since it removes the part of the stomach that produces the hunger stimulating hormone ghrelin
  • Digestion occurs normally as the digestive system is not altered
  • Does not cause malabsorption or nutritional deficiencies as it does not involve rerouting or bypassing the small intestine
  • Less chance of developing ulcers than with gastric bypass surgery
  • Dumping syndrome not likely to occur as the stomach outlet (pyloric valve) remains intact, unlike gastric bypass surgery
  • Less complicated procedure than gastric bypass or duodenal switch surgery
  • Can usually be performed laparoscopically on extremely obese patients
  • Does not require a gastric band being implanted into the body
  • Does not require adjustments or fills as with a LAP-BAND or REALIZE Band
  • Safer than a combined restrictive/malabsorptive weight loss surgery for patients who have many health problems
  • May be converted to gastric bypass or duodenal switch if necessary for additional weight loss
  • Expected excess weight loss for stand-alone procedure is 60 to 70% at two years


  • As it is a purely restrictive weight loss procedure, inadequate weight loss or weight regain is more likely than with a procedure involving intestinal bypass
  • With time, new smaller stomach pouch may stretch (also occurs with gastric bypass surgery)
  • Although the gastric sleeve helps control hunger and limit amount of food that can be eaten at any one time, weight loss will not occur without a healthy, low-calorie diet and regular exercise (same as with other purely restrictive procedures such as LAP-BAND and REALIZE Band)
  • If performed as the first part of a two-stage process, a second malabsorptive weight loss surgery such as the duodenal switch will need to be performed at a later time
  • The surgery is not reversible as a portion of the stomach is permanently removed
  • Leaks or bleeding may occur along the stomach stapling edge
  • Procedure may not be covered by some insurance companies
  • All surgery and anesthesia involves some level of risk including bleeding, blood clots, infection, pneumonia, or complications
  • Lack of published data for long-term weight loss results

Gastric Sleeve Video

The following video is an overview of Laparoscopic Gastric Sleeve Surgery.

Patient Considerations

  • Safer option for individuals with BMI greater than 60 to undergo two-stage process of gastric sleeve followed up with duodenal switch or gastric bypass after partial weight loss
  • Option for patients concerned about long-term side effects of weight loss surgery that involves rerouting and bypassing a portion of the small intestine, such as intestinal obstruction, ulcers, anemia, osteoporosis, protein deficiency, and vitamin deficiency
  • Restrictive weight loss option for patients who are not comfortable having a medical device implanted into their body as with the LAP-BAND or REALIZE Band
  • Surgical weight loss option for patients with health problems or complex medical issues that may prevent them from having other types of weight loss surgery, such as anemia, Crohn's disease, anti-inflammatory drug use, or extensive prior surgery
  • Revision option for gastric band patients experiencing problems with their band but who do not want to convert to a bypass type of operation

Gastric Sleeve Surgery Diet

The gastric sleeve procedure will help a person control their hunger and limit the amount of food they can eat at any one time. As with all surgical weight loss programs, however, weight loss ultimately depends on adopting a new lifestyle, healthy diet, and regular exercise. The surgery itself does not require many food restrictions as the stomach continues to function normally, but for weight loss to occur high-calorie and high-fat foods and drinks must be avoided and daily calories must be limited. Many bariatric surgeons recommend eating five small, healthy meals a day with no snacking in-between meals.

Following surgery, patients will need to follow a liquid diet for about two weeks while the body heals. The diet will slowly progress from soft to solid foods. At about 4 to 6 weeks after surgery, most patients will usually be able to eat a regular solid diet. During the first 1 to 2 years after surgery, when most weight loss is expected to occur, the diet is limited to 600 to 800 calories a day. Once goal weight is achieved, most patients are able to eat about 1000 to 1200 calories a day.


The cost of gastric sleeve surgery is comparable to other types of weight loss surgery; typically, it will cost anywhere from $10,000 to $25,000 to undergo gastric sleeve surgery in the United States. This cost is within a range similar to the average cost of lap band surgery ($15,000 to $25,000) and the average cost of gastric bypass surgery ($20,000 to $35,000).

Based upon the wide fluctuation in costs, it is obvious to see that there is not one set price to pay for gastric sleeve surgery. The amount will vary depending on many factors including the geographic region, patient health, fees paid to surgeon and medical facility, level of care, and complications.

Insurance Coverage

The Gastric Sleeve procedure as a stand-alone weight loss surgery is a newer approach and still considered experimental by some bariatric surgeons and insurance companies. It is covered by some weight loss surgery insurance plans, but not by others. Typically, insurance companies do not cover any medical procedures that they consider experimental. Patients who are interested in this procedure and do not have health coverage that will cover the cost may want to consider healthcare financing.

Weight Loss Results

Patients who undergo the gastric sleeve procedure as a first stage procedure are typically expected to lose approximately 30 to 50% of their excess body weight during the following six to twelve months before continuing with the second surgery. This initial weight loss will make it safer to proceed with the second-stage of the process, either gastric bypass or duodenal switch surgery, which involves rerouting the small intestine. The timing of the second procedure will depend on the rate of weight loss following the gastric sleeve surgery.

Short term results show that gastric sleeve patients who have had the stand-alone procedure can expect to achieve a 60 to 70% excess weight loss at 2 years. Long term results are not yet available. If weight loss is insufficient following gastric sleeve surgery, a malabsorptive weight loss procedure such as the duodenal switch may be performed in order to promote further weight loss.

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