Gastric Bypass vs Duodenal Switch Surgery Comparison

Gastric Bypass vs Duodenal Switch

After you determine your candidacy for bariatric surgery, the bariatric surgeon will recommend weight loss procedure options that best suit you based on your health, BMI, and devotion to the procedure. Here, we will explain each procedure in detail and its pros and cons so you can see which weight loss surgery option fits you best. Remember, each procedure makes biological differences in anatomy that affect the body and impact your lifestyle.

Long-term results show duodenal switch’s superior weight loss and metabolic control when compared to RNY gastric bypass. DS/BPD results in higher BAROS* global assesment score making it more sutiable for super obese patients.

Roux-en-Y Gastric Bypass (RYGB) is often compared to the newer procedure Duodenal Switch w/ BilioPancreatic Diversion (DS/BPD). Both are very similar in weight loss methods, but they have slight differences that make each surgery ideal for particular individuals. The duodenal switch procedure has more adverse events and is reserved for morbidly obese patients (BMI>50) or patients who want to be skinny.

* BAROS (Bariatric Analysis and Reporting Outcome System)

How Gastric Bypass Surgery Works

Gastric Bypass Surgery, otherwise known as laparoscopic Roux-en-Y Gastric Bypass, is the gold standard in bariatric surgery with good reason.

Gastric Sleeve Surgery Schematic
  • Less Invasive Surgery

  • Comparable Expected Weight Loss

  • Low Complication/Side Effect

  • Gold Standard of Bariatric Surgery

Ever since 1994, gastric bypass has been performed and perfected, allowing researchers to study the long-term results. This allows patients the peace of mind to choose a well-established weight loss surgery.

How Duodenal Switch Surgery Works

Duodenal Switch Surgery is a very powerful weight loss surgery that combines restrictive and malabsorptive methods to produce high expected weight loss.

Duodenal Switch Surgery Schematic
  • Highest Amount of Excess Weight Loss (%EWL)

  • Highest Reduction in Comorbidities and Health-Related Problems

  • Most Invasive Weight Loss Procedure

Duodenal switch is the most complicated weight loss surgery that is similar to gastric bypass but with less practicing surgeons.

Which Procedure is Best for Me?

Gastric bypass surgery has a lot more long-term data and results than its newer counterpart, duodenal switch surgery. The patient needs to weigh out the risks and rewards of each surgery.

The duodenal switch has more expected weight loss than gastric bypass surgery, although it also has many more potential complications than RNY. The RNY bypass has been known as the gold standard of bariatric surgery and has been around since 1967.

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Candidacy Requirements

Do I Qualify for Gastric Bypass?

Do I Qualify for Duodenal Switch?

  • BMI 40+

  • Type 2 Diabetes or Hypertension

  • Previous Ulcer

  • Dedicated to Following Strict Lifelong Habits

What is the Biggest Difference?

Gastric bypass surgery is the most popular weight loss surgery but doesn’t provide the highest expected weight loss. Duodenal Switch provides the highest average expected weight loss available but comes with more risks and complications.

Acid Reflux and GERD (Pyloric Valve Regulating Food)

In the duodenal switch, the stomach size is reduced and the pyloric valve, or pylorus, stays untouched. Restriction in the stomach increases gastric pressure and reduces gastric emptying. In gastric bypass, the pyloric valve stays connected to the separated stomach, and the new pouch redirects most of the stomach acid to stay out of the esophagus. Therefore, Roux-en-Y gastric bypass is best for patients with acid reflux or gastroesophageal reflux disease.

Dumping Syndrome

Dumping syndrome is an abdominal discomfort accompanied by rapid heart rate, palpitation, nausea, vomiting, and explosive bowel evacuation. It is estimated that over 50% of gastric bypass patients experience dumping syndrome due to the unregulated flow of food from the stomach to the small bowel.

  • Early Dumping Syndrome – Instantly after eating food. Symptoms include abdominal pain, cramping, nausea, and light-headed.
  • Late Dumping Syndrome – 1 to 2 hours after eating food. Symptoms include lack of energy, exhaustion, perspiration, and feeling “out of it.”

Staying on the post-op diet usually fixes this problem and patients usually outgrow symptoms.


If the patient has had or currently has ulcers, the duodenal switch is recommended over gastric bypass surgery. The pouch that is formed with bypass surgery is so small, it is referred to as the “blind” stomach. It is nearly impossible for ulcers to be detected without a doctor laparoscopically scoping the stomach under anesthesia. Taking Aspirin or Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) increases the risk of ulcers.

Curing Obesity-Related Health Problems

Both procedures cure comorbidities like Types II Diabetes and hypertension, however, duodenal switch surgery is much more effective with remission of obesity-related diseases. The duodenal switch also shows much quicker results in its metabolic effect.

Table Comparison of Gastric Bypass versus Duodenal Switch

Statistics show that since 2005, sleeve gastrectomy and Roux-en-Y gastric bypass have been the most widely requested and effective treatments of morbid obesity and type 2 diabetes mellitus. Gastric Bypass Surgery, once known as the “gold standard”, accounted for 80% of all bariatric procedures performed in the United States. Today, Gastric Sleeve Surgery accounts for over 90% of all weight loss surgeries performed across the country.

Gastric BypassDuodenal Switch
MethodRestrictive & MalabsorptiveRestrictive & Malabsorptive
StomachNew Pouch
(1 oz.)
Remove 70%
(4-5 oz.)
AnatomyReroute IntestinesSwitched Intestines
Duration2.5 hours3 hours
Hospital2 to 3 days2 to 4 days
Time Off2 to 3 weeks3 to 4 weeks
Recovery3 to 4 weeks4 to 6 weeks
AdvantageGold Standard
Fewer Complications
Higher %EWL
More Effective
DisadvantageDumping Syndrome
Hard to Revise
Not Reversible
Most Complications
Vitamins Required
Not Revisable
Weight Loss64-91% (%EWL)75-100% (%EWL)
Post-Op3 to 5 Meals/Day
Avoid Sugar and Fats
Vitamin Supplements
3 to 5 Meals/Day
800-1200 Cal
Strict Vitamins
Cure RateT2DM: 68%
HTN: 45%
GERD: 56%
OSA (CPAP): 77%
T2DM: 82%
HTN: 67%
GERD: 56%
OSA (CPAP): 92%
CandidacyBMI of 35+
“Sweet Tooth”
Severe Acid Reflux
BMI of 45+
Last Resort
  • (%EWL) = % Excess Weight Loss

  • T2DM = Type 2 Diabetes Mellitus
  • HTN = Hypertension

  • OSA = Obstructive Sleep Apnea

Comparing Costs and Insurance Coverage

The costs of gastric bypass surgery range from $5,995 to $19,000 depending on where the surgery takes place. In Mexico, the price is as low as $5,595 and maintains a high-quality procedure. In the United States, self-pay ranges from $15,000 to $30,000 for gastric bypass surgery. Duodenal switch surgery costs anywhere from $6,000 to $35,000 around the world. At Mexico Bariatric Center, we pioneered the duodenal switch surgery in Mexico and have some of the most highly trained surgeons specializing in duodenal switch surgery. Our price is only $6,695.

The criteria for bariatric surgery insurance coverage follow strict guidelines for patients who get accepted. The process takes at least one year just to be approved by most insurance providers. Patients must follow the pre-op diet, fail a strict diet program, and meet with many medical professionals, psychologist, and a dietitian before approval.

RNY Bypass vs Duodenal Switch Cost Comparison

Complications and Side Effects

Complications After Gastric Bypass

There are many fewer complications associated with gastric bypass vs duodenal switch surgery. The risks and complications include excessive/internal bleeding, infection, blood clots, dumping syndrome, malnutrition, and ulcers.

Complications After Duodenal Switch

As a newer bariatric procedure, the DS has a variety of complications that occur more often due to less experienced surgeons. The duodenal switch complications include nutrition deficiency, leakage, infection, hemorrhaging, blood clots, and protein malabsorption.

  • Excessive bleeding (~2% to ~6%)

  • Infection (~2% to 4%)

  • Adverse reactions to anesthesia (~1.2%)

  • Blood clots (2%)

  • Leaks in the gastrointestinal system (~3% to 6%)

Digestive Tract and Anatomy