DUODENAL SWITCH

Pros

• The procedure can help you lose more weight than other bariatric surgeries—up to 70% excess weight loss or greater over five years, according to one study of patients with a BMI of 50+. 
• Within four years after surgery, the duodenal switch seriously reduces the risk of related conditions, including type 2 diabetes, high blood pressure, and high cholesterol—by 82%, 67%, and 81%, respectively, according to another study.
• The surgery reduces the production of the gut hormone ghrelin—which, in turn, reduces your appetite and makes you feel less hungry. It’s also shown to increase the amount of “good bacteria” that live in your GI tract (microbiome). 
• Initially, the procedure helps reduce the amount of food consumed, but over time, this effect lessens—so you’ll eventually be able to eat near-normal amounts of food, a major difference from other weight-loss procedures. 
• A duodenal switch can be an effective option for patients who failed to lose weight with other procedures. “It’s an excellent revision surgery when gastric sleeve or lap band patients fail,” says Dr. Lopez.
• More surgeons are offering it. “I believe that as young bariatric surgeons deal with weight regain after [gastric] sleeve surgery, there will be a big increase in the number who decide to add duodenal switch to their practice, as conversion to bypass from sleeve yields less than desirable results for weight regain,” says Dr. Roberts. 
• RealSelf members have been so impressed with their results that they give it a 100% Worth It Rating. “I’d do it again, in a heartbeat,” says RealSelf member mbach74, who lost 170 pounds with BPD/DS after her lap band failed. “My bloodwork is perfect. The only not-so-great side effect—horrible-smelling gas and stool. But it’s a small price to pay for the amazing success I’ve had!”

Cons

• The surgery takes longer than other bariatric surgeries—up to four hours, under general anesthesia. 
• Recovery can take up to four weeks. 
• After surgery, you’ll need to take vitamin and mineral supplements and have regular blood testing for the rest of your life. Even if you take all the supplements as prescribed, there’s a possibility that you could develop nutritional deficiencies and related health issues that require treatment, such as anemia, osteoporosis, or kidney stones.
• Because the operation limits food absorption, you may experience more frequent and loose bowel movements and increased flatulence. Working closely with your healthcare providers can help avoid intestinal discomfort, but this may require an additional corrective surgery. 
• Duodenal switch increases the risk of developing acid reflux (heartburn). 
• As with all weight-loss surgery, duodenal switch can leave you with excess skin that may require body lift surgery to remove. If the excess skin causes medical issues (something that’s more common on the breasts and abdomen), plastic surgery to remove it may be covered by insurance; otherwise, the surgery is considered elective and won’t be covered.
• Duodenal switch is a tool for weight loss, not a fail-safe. You still have to eat healthy and stay active in order to maintain your results. 
• The duodenal switch is a complex surgery. Find a board-certified surgeon who specializes in the procedure.

If your health insurance covers bariatric surgery, it may also cover at least part of this procedure. If a duodenal switch is being performed because a gastric bypass was unsuccessful, insurance will often cover the initial surgery but not this revision procedure. Check with your plan provider to see what it will cover.

The ideal candidate for a duodenal switch is:

• Relatively young. “Patients are preferably between 30 and 50 years old,” says Dr. Lopez.
• Severely obese. Your BMI (body mass index) should be between 35 and 60. “A patient with a BMI over 60 would need to do the procedure in two steps,” explains Dr. Lopez. “They’d first have the gastric sleeve, then have the duodenal switch a year later.”
• Generally healthy. Duodenal switch surgery is still a good option for people who have some obesity-related health problems like diabetes, but you need to be healthy enough to tolerate surgery.

The procedure is not for everyone. After the surgery, you’ll need to adhere to a very strict vitamin and mineral regimen for the rest of your life, to prevent malnutrition. “It’s important to have access to a nutritionist or medical support as well as to good-quality food and supplements, to avoid developing nutritional complications,” says Dr. Lopez. 

The switch is also a poor fit for patients with certain health concerns. Patients with severe acid reflux (heartburn) and esophageal or gastric motility problems like achalasia or gastroparesis are not good candidates for duodenal switch surgery, which may worsen reflux in up to 20% of patients; they would be better candidates for gastric bypass surgery.

A qualified weight-loss surgeon can assess whether you’re a good candidate.

The surgery is performed in either a hospital or surgery center, under general anesthesia, as either open surgery (requiring an large incision in your abdomen) or laparoscopically (with five really small incisions).

The operation is performed in two steps.

• First, a large portion of the stomach is removed so that it takes the shape of a narrow tube or sleeve—the same procedure as in a sleeve gastrectomy. By reducing the size of your stomach, you’ll feel fuller faster with smaller portions of food, which decreases your calorie intake and helps you lose weight. 
• Next, the part of the small bowel that normally connects to the stomach (called the duodenum) is divided about 10 feet from the lower portion of the intestine, to create the bypass. Consumed food would normally go from the sleeve into the initial part of the small intestine but is rerouted, or “switched,” to the lower part of the small intestine, allowing food to bypass up to three-quarters of the intestine, where calories and nutrients are normally absorbed. 

The switch can be performed in two stages, with the intestinal bypass portion performed up to a year later. 

By having food empty directly into the last segment of the small intestine, bile from the liver and digestive juices from the pancreas process food lower in the body, giving them less time to pull out calories. The procedure also lowers the overall absorption of fat, so patients absorb only about 20% of the fat they consume. 

Unlike in a gastric bypass surgery, duodenal switch surgery conserves the pyloric valve, which regulates the release of stomach contents into the small intestine. Leaving this valve intact means that people with a duodenal switch don’t experience dumping syndrome, which happens when your stomach empties its contents faster than normal, causing symptoms like nausea and abdominal cramping. 

“Patients with the duodenal switch experience two to three bowel movements per day,” says Dr. Ricardo Bonnor, a general surgeon in Houston. “Sometimes the frequency of bowel movements requires revision surgery."

You’ll spend two days recovering in the hospital so you can be monitored. Some discomfort is common, and you’ll be given medication to control the pain. Your surgeon will perform a number of different tests, to check for leaks (perforations in the stomach or bowel) and make sure everything is working properly before you head home. 

Your surgeon will also give you post-op dietary instructions. You’ll likely be on a liquid diet for a few weeks after surgery, and over time, you’ll start to eat soft foods and then solid foods. The remaining stomach is much larger after duodenal switch surgery than with gastric bypass, and this allows for larger meals. Still, eating too much or too fast may cause stomach cramps or vomiting. You’ll also be directed to take nutritional supplements.

You can resume regular activities in five to seven days, but avoid heavy lifting for six weeks. 

RealSelf Tip: “Close monitoring after being discharged from the hospital is very important, so be sure to follow up regularly with your surgeon or other healthcare provider,” says Dr. Lopez.

Patients can expect a loss of around 85–95% of excess weight in the first two years, says Dr. Lopez. “Around 80–90% of patients keep their new weight in the long term—10 or more years after surgery,” especially if they've also made healthy lifestyle changes.

Weight loss is usually rapid in the first year, with most patients losing up to 70% of their excess body weight within 12 months. RealSelf members have reported losing 40 pounds the first month after surgery and 100 pounds after six months as well as losing and maintaining a 135-pound weight loss for two and half years.  

Once weight loss starts, health problems like type 2 diabetes or high blood pressure that were directly caused by excess weight often resolve.

It’s important to be prepared for the excess skin that major weight loss can leave you with. Such was the case with one RealSelf member who weighed 400 pounds and went from a size 28 to a 12/14 after duodenal switch surgery. “My once taut, plump bits are now soft, saggy bits,” she reports. “If you’re doing this for vanity, this may be an issue for you and you may need plastic surgery."

This surgery is generally safe when it’s performed by an experienced, board-certified surgeon. However, like all major surgery, bariatric surgery has numerous possible risks, including infection, adverse effects of anesthesia, excessive bleeding, blood clots, difficulty breathing, and gastrointestinal (GI) leakage. GI leaks, one of the most feared complications, occur in less than 2% to 6% of cases. Rarely (in 0.5% of cases), complications from the surgery can be fatal.  

Be sure to talk with your doctor and weigh these risks against those that come with chronic obesity, which has about a 5% mortality rate. 

Like all bariatric surgery, duodenal switch alters the gastrointestinal tract, so your body won’t absorb as much protein or as many essential vitamins (like A, D, E, and K) and minerals (like calcium and iron). As a result, patients are at much higher risk for diseases like anemia, osteoporosis, and protein malnutrition. You’ll need to take supplements every day, without missing a single day, to avoid malnutrition. According to the American Society for Metabolic and Bariatric Surgery (ASMBS), health problems due to deficiencies usually occur in patients who don’t regularly follow up with their surgeon to establish healthy nutrient levels.

Many obese patients are already nutritionally deficient prior to surgery, so a pre-surgery  nutritional assessment and correction of deficiencies is required. 

RealSelf Tip: “The duodenal switch is a very effective surgery—but you need to have it done by a surgeon who has ample experience and performs it frequently, to reduce your surgery risks and optimize your results,” says Dr. Ungson.

Yes. However, according to the ASMBS, it’s recommended that you wait 12–18 months after surgery before getting pregnant, to avoid complications. Most women are more fertile after surgery, so be sure to use protection during intercourse after bariatric surgery. 

As a bonus, kids born after their mother’s surgery are less at risk of being affected by obesity later, due to activation of certain genes during fetal growth. There’s also less risk of needing a C-section.

“Bariatric Surgery Misconceptions: ASMBS.” American Society for Metabolic and Bariatric Surgery.

“Calculate Your BMI - Standard BMI Calculator.” National Heart Lung and Blood Institute, U.S. Department of Health and Human Services.

Risstad, Hilde. “Five-Year Outcomes After Gastric Bypass and Duodenal Switch in Obese Patients.” JAMA Surgery, American Medical Association, 1 Apr. 2015.

Wendling, Patrice. “Duodenal Switch May Excel at Type 2 Diabetes Resolution.” MDedge Endocrinology, 2 Jan. 2019.