Duodenal switch surgery may be a better surgical procedure for achieving weight loss and control of comorbidity conditions, especially among the super-obese, according to a study published in the September issue of the Archives of Surgery.

The following chart provides a side-by-side comparison between the two procedures:

 RNY Gastric Bypass Duodenal Switch
Surgical RiskModerateHigh
Rate of
Weight Loss
Weight Loss
60-85% of excess body weight within 12-18 months75-90% of excess body weight within 18 months
Operating Time1-2 hours3-4 hours
Recovery Time9-12 weeks3-4 weeks
Hospital Stay3 nights2 nights
Time off Work2-3 weeks3 weeks
ReversibleCould be, but high riskNo
Medical ImplantNoNo
How it
Weight Loss
  • Restrictive & Malabsorption
  • Limits food intake
  • Reduces absorption of calories and nutrients
  • Restrictive & Malabsorption
  • Limits food intake
  • Food bypasses 45-60% of the small intestine, resulting in higher malabsorption and greater weight loss
to Intestine
  • Small intestine is cut and bypassed during RNY gastric bypass surgery
  • Reroutes "switch" a portion of the small intestine during duodenal switch surgery
to Stomach
  • New Stomach Created
  • Stomach is divided into a small upper pouch 1 oz (20-30 cc) and a larger lower pouch
  • Stomach Size is Reduced
  • 70-80% of the stomach is removed, creating a new small stomach (similar to gastric sleeve)
Bariatric Diet & Dietary Guidelines
  • 800 calories per day during weight loss (12-18 months)
  • 3 small protein meals per day
  • Avoid sugar and fats to prevent dumping
  • Avoid carbonated drinks
  • Drink 6-8 cups of water a day
  • Eat 1000-1200 calories per day after 18 months

New Eating Habits After Bariatric Surgery
  • Eat small portions daily
  • Chew food throughly to puree consistency before swallowing
  • Eat slowly
  • Eat high-protein foods
  • No drinking with meals, drink water 30 minutes before or after meals

  • Eat small portions daily
  • Eat 4-6 times a day
  • Chew food throughly to puree consistency before swallowing
  • Eat slowly
  • Eat high-protein foods
  • No drinking with meals, drink water 30 minutes before or after meals

Bariatric Vitamins, Minerals & Nutritional Supplements
  • Multivitamin
  • Calcium
  • Iron
  • Vitamin B12
  • Multivitamin
  • Calcium
  • Iron
  • Vitamin A, D, E, K
Pros, Benefits, Advantages of
Weight Loss Surgery
  • Rapid weight loss during the first 6 months
  • Reduces food intake
  • Reduces calorie intake
  • Proven long-term effectiveness maintaining weight loss
  • Most common and widely accepted weight loss surgery

  • Most powerful weight loss operation
  • Most effective procedure for improving or eliminating diabetes (99% cure rate)
  • Patients report longer lasting fullness
  • Stomach surgery may reduce hunger by removing hunger-causing hormones
  • About 200-400 calories may be lost via malabsorption

Cons, Risks, Disadvantages of
Weight Loss Surgery
  • Blood clots
  • Bowel obstruction
  • Dumping syndrome
  • Infection
  • Leaks
  • Nutrient deficiencies
  • Reflux (GERD)
  • Ulcers
  • Diarrhea
  • Intestine blockage
  • Protein and vitamin deficiency
  • Highly technical operation
  • Stomach removal is permanent, but intestinal bypass may be reversed
  • Preoperative weight loss is critical to complete the procedure laparoscopically
Am I a Candidate for Weight Loss Surgery?
  • Gastric bypass is most effective for patients with a BMI of 35-55
  • Duodenal switch is best for patients with BMI > 50
  • Patients with BMI < 45 may lose too much weight

Surgery Method
Laparoscopic Bariatric SurgeryLaparoscopic Bariatric Surgery
Learn More About Different Types of Bariatric SurgeryTypes of Bariatric SurgeryTypes of Bariatric Surgery

Gastric Bypass Surgery

Gastric Bypass Surgery is widely considered the “gold standard” and most common bariatric procedure in North America. Patients who choose gastric bypass vs duodenal switch typically have lower BMIs and are exposed to lower surgical risks compared with duodenal switch surgery.

Duodenal Switch Surgery

Duodenal Switch Surgery is a highly effective surgical weight loss option for morbidly obese patients with BMIs > 50. Studies show that duodenal switch results in superior long-term weight reduction and greater resolution or improvement in obesity-related comorbidities compared with gastric bypass surgery. However, the risk profile is higher for duodenal switch vs gastric bypass.

Considering Gastric Bypass or Duodenal Switch

No matter what type of bariatric surgery you choose – duodenal switch versus gastric bypass… making a serious commitment to behavior and diet modifications is critical to sustained weight loss.

Compare Differences Between Types of Bariatric Surgery