Gastric Sleeve Surgery vs Gastric Bypass Surgery

Choosing between gastric sleeve vs RNY gastric bypass is a huge decision to make, as the implications will affect the future of your life. It’s important to know exactly what you are signing up for when determining which bariatric procedure is best for you.

Statistics show that since 2005, gastric sleeve and gastric bypass are being out-chosen for bariatric surgery. Gastric bypass surgery used to account for 80% of all the bariatric surgeries in the United States. Gastric sleeve surgery accounts for over 90% of all bariatric surgery procedures performed today.

Here we will show the pros and cons, similarities and differences, and long-term results you can expect for both gastric sleeve surgery and gastric bypass surgery.

which option is best for me - sleeve vs bypass

Procedures Explained: Pros and Cons

Gastric Sleeve Surgery

Gastric Sleeve Surgery VSG - Sleeve vs Bypass

Vertical Sleeve Gastrectomy (VSG) is a permanent weight loss surgery that downsizes the stomach by as much as 85%. This restriction helps in two ways: first, the smaller stomach capacity contributes to making patients feel fuller faster – therefore reducing caloric intake.

Secondly, the hunger hormones (Ghrelin) are reduced, allowing patients to be free of hunger desires.

Gastric Bypass Surgery

Gastric Bypass Surgery RNY - Sleeve vs Bypass

Gastric Bypass Surgery is a very powerful weight loss surgery that uses two surgical methods to achieve big weight loss for patients. Gastric Bypass uses restriction and malabsorption to reduce caloric intake considerably.

Gastric bypass is intended for patients who are suffering from co-morbidities, along with very debilitating obesity.

Notable Differences

The notable difference between these two operations is that gastric bypass provides slightly more expected excess weight loss (%EWL) than the gastric sleeve – although comes with more potential risks and complications. A Rand Corporation study found that patients lose on average 20 pounds more with Roux-en-Y gastric bypass than with vertical sleeve gastrectomy.

Gastric sleeve surgery is less invasive than gastric bypass and there is no rerouting of the intestine. After gastric bypass, there is fat malabsorption which does not occur in sleeve surgery (VSG). As a result of bypass malabsorption, essential nutrients and minerals are not absorbed by the body. Therefore, it is important to take vitamins and dietary supplements lifelong.

There is a chance to stretch the new stomach (stoma) in gastric bypass and not so much in gastric sleeve as the pyloric valve stays intact.

Which Procedure is Best For You?

Sleeve Gastrectomy

  • Less Invasive Surgery

  • Low Complication/Side Effect

  • Lowest Cost of Procedure

  • Most Popular Surgery

Roux-en-Y Bypass

  • Highest Amount of Excess Weight Loss (%EWL)

  • Highest Reduction in Comorbidities & Health-Related Problems

Candidacy Requirements

Gastric sleeve is good for patients with extensive scars from a previous surgery in the abdominal area. Sleeve is also suitable for patients with ulcer history, taking aspirin, or smoke.

  • BMI 30+

  • Existing abdominal scarring

  • Previous Ulcer

  • Sleeve is easily revisable

RNY gastric bypass is better for patients with severe acid reflux and GERD. Patients with slow metabolism are better off with gastric bypass. Also, if patients have previously had gastric fundoplication surgery, meaning the stomach is wrapped around the esophagus valve to control acid reflux, then gastric bypass is the best option for them.

Gastric Sleeve vs Gastric Bypass: Table Comparison

Gastric SleeveGastric Bypass
Method of Weight LossRestrictiveRestrictive & Malabsorptive
 Stomach AlterationsSmaller Stomach

  • 70-85% is removed
  • 2-3 oz / 60-100cc
 New Pouch: Stoma

  • stomach is bypassed
  • 1 oz / 20-30cc
 Changes to Intestine No ChangeStoma is rerouted to intestine
 Operating Time 1.5 hours 2.5 hours
 Average Hospital Stay 1 to 2 days 2 to 3 days
 Time off Work 1 to 2 weeks 2 to 3 weeks
 Recovery Time 3 weeks 4 to 6 weeks
  • No intestinal changes
  • Simpler procedure
  • Fewer complications/side effects
  • Higher Expected Weight Loss
  • More effective on comorbidities
  • Newer surgery with limited long-term data.
  • Daily Supplements and Vitamins Required
  • Dumping Syndrome is Common
  • Harder to revise if failed
 Realistic Expectations
  • 60%-70% of excess weight 2 years.
  • Malabsorption of nutrients
  • 70% of excess weight in 2 years
 Post Surgery Dietary Info
  • 3 to 5 meals a day
  • 600-800 calories first 2 years
  • 1000-1200 after 2 years
  • Must take vitamin and protein supplements
  • 3 to 5 meals a day
  • Must avoid sugar and fats
  • Must take vitamin and protein supplements
Resolution of Co-morbidities
  • T2DM 75%
  • HTN 56%
  • GERD 56%
  • OSA (CPAP use) 62%
  • T2DM 93%
  • HTN 45%
  • GERD 56%
  • OSA (CPAP use) 77%
Candidate Efficacy
  • BMI of 30+
  • For high risk / high BMI patients
  • As a “first-stage” procedure
  • BMI of 35+
  • Patients with a “sweet tooth”
  • Patients with severe acid reflux
Gastric Sleeve CostsGastric Bypass Costs
Mexico Bariatric CenterStarting $4,795Starting $5,795
Costa Rica$10,000$13,000
United States$19,000$24,000

Insurance Coverage

Having insurance cover for weight loss surgery is a difficult process in the United States. You should first make sure your doctor agrees with your decision to get bariatric surgery. Then, speak with your insurance provider to see if you have coverage for gastric sleeve surgery or gastric bypass surgery. If you have insurance coverage, it generally takes about one year to be approved – after a long pre-op diet, check-ups, classes, psychologist, and nutritionist meeting.

Mexico Bariartic Center can help you decide which surgery is best for you quick and hassle-free.

Gastric Sleeve Surgery Complications

Gastric sleeve surgery has the lowest potential complications compared to other weight loss surgery procedure. Mainly, because it only removes a portion of the stomach. There is slightly less excess weight loss than gastric bypass. The complications include; sleeve leakage, hemorrhaging or bleeding, and stroke or heart problems.

Gastric Bypass Surgery Complications

Gastric bypass is one of the more established bariatric procedures. Although most surgeons have extensive experience with bypass surgery, there are still more complications than gastric sleeve surgery. The complications include gallstones, stomal stenosis, pouch stretching, leakage, nutrition/protein deficiencies, dumping syndrome, vomiting, and ulcers.

Sleeve vs Bypass Digestive Tract

Gastric Sleeve Surgery

Gastric Sleeve Digestive Tract Image

New stomach is like a hot dog or a “sleeve” and has the same shape as the duodenal switch pouch but smaller. With vertical sleeve gastrectomy surgery, there is no anatomical changes, no changes to pyloric valve, and no intestinal bypass.

The gastric sleeve surgery significantly restricts the volume of food that can be eaten. The mixing of food with bile and pancreatic enzymes occurs as before surgery with no changes. Therefore, there is a no malabsorption of nutrients, dumping, or bowel movements.

Gastric Bypass Surgery

Gastric Bypass Digestive Tract - Sleeve vs Bypass

New stomach is a small pouch and is connected to the small intestine where food and digestive juices are separated for the first 3 to 5 feet. The RNY significantly restricts the volume of food that can be eaten.

The delay in mixing of food with bile and pancreatic enzymes induces a moderate fat and protein malabsorption as well as calcium, iron, and B-complex vitamins absorption reduction. The alterations in intestine also change the bowel movements: different smells, more gas, and occasional cramping.