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The facts about weight-loss surgery for the severely obese

Obesity is a serious health threat: It can shorten your life span significantly and have a dramatic impact on your quality of life. Specifically, it can threaten your heart health by putting you at greater risk for developing cardiovascular disease, high blood pressure, high cholesterol and diabetes.

But there may be hope for the severely, or morbidly, obese: a solution called bariatric surgery. Bariatric surgery has been in the spotlight lately, as a result of the publicity surrounding well-known people such as weather reporter Al Roker and singer Carnie Wilson, who have had the procedure. But just because the surgery was right for them doesn’t mean it will be right for you. Bariatric surgery is a serious procedure that requires a lifelong commitment to a new way of eating and monitoring your health.

Weight-loss surgery is not cosmetic surgery. It is performed only on patients with a body mass index (BMI) of at least 40, which translates into approximately 100 or more pounds overweight. People who have a BMI of 35 to 40 may also be eligible for surgery if they have obesity-related health conditions and have had no success with medication, behavior modification, diet and exercise.

What is bariatric surgery?

Bariatric surgery promotes weight loss by restricting food intake into the stomach (restrictive surgery), by rerouting food to reduce caloric absorption (malabsorptive surgery) or both (combined surgery). Malabsorptive surgery can cause severe nutritional deficiencies and is no longer recommended.

Restrictive surgery. These procedures restrict the amount of food you can eat but don’t interrupt normal digestion. The most popular type of restrictive surgery is adjustable gastric banding (AGB). With a silicone band, surgeons create a small pouch at the top of the stomach where food enters from the esophagus. The pouch will expand to hold two to three ounces of food. The lower end of the pouch usually has an opening of only about half an inch, which slows the rate of food as it leaves the pouch, creating a feeling of fullness.

In vertical banded gastroplasty (VBG), both a band and staples are used to create the pouch. Once a common procedure, VBG is not often used today.

With both AGB and VBG, patients must follow lifelong dietary guidelines restricting the amount of food they can eat (usually about one half to one cup of food per meal). Vomiting is one risk of restrictive surgery and occurs when the small stomach pouch is stretched by too much food.

In VBG, the band may wear away or the staple line can break. Stomach juices may leak into the abdomen, requiring emergency surgery, but the risk of this happening is low. After AGB, the band can eventually slip and the saline used to adjust the band can leak.

Patients who undergo restrictive bariatric surgery generally lose less weight, and are less likely to maintain their weight loss, than those who have combined procedures.

Combined surgery. This type of operation combines stomach restriction with a partial bypass of the small intestine and is more complex than a restrictive procedure alone. Surgeons connect the opening at the bottom of the stomach to the small intestine’s lower end, bypassing the part of the digestive tract where calories and nutrients are absorbed.

Combined surgeries include:

  • Roux-en-Y gastric bypass. RGB is the most common combined surgery procedure. Surgeons use staples to create a small stomach pouch. Then, they attach a Y-shaped section of the small intestine to the pouch, forcing food to bypass the rest of the stomach and digestive tract. A big advantage for RGB patients is that it leaves them with an early sense of fullness and satisfaction when they eat.
  • Biliopancreatic diversion. A more complicated operation, BPD involves removing parts of the stomach. Surgeons connect the remaining pouch to the end section of the small intestine. A common variation of BPD is biliopancreatic diversion with duodenal switch, or BPDDS, which leaves more of the stomach intact.

As with restrictive surgery, most people are no longer able to eat large amounts of food. About three-quarters to one cup of food can be eaten without discomfort or nausea. Any malabsorptive surgery, especially BPD, comes with a risk of nutritional deficiencies. Patients must take vitamin and mineral supplements for the rest of their lives to counteract the loss of nutrients. Patients may also experience nausea, weakness, faintness, sweating and diarrhea after a meal if food moves too quickly through the digestive system (called “dumping syndrome”). Success rates depend on the patient’s ability to stick to a special diet.

The bottom line

No weight-loss method—including surgery—comes with a guarantee. Patients who achieve the most success are able to show a dedication to changing their eating habits and undergoing medical follow-up. It’s a commitment that has to be made for the rest of patients’ lives.

Are you ready for bariatric surgery?

If you are considered severely obese and fit the profile for surgery, the National Institute of Diabetes and Digestive and Kidney Diseases suggests answering these questions to help you decide if weight-loss surgery is for you. Are you:

  • unlikely to lose weight without having surgery?
  • informed about the different procedures and the effects of treatment?
  • committed to losing weight and improving your health?
  • aware of the changes you’ll have to make after surgery, such as new lifelong eating habits and behavior modifications?
  • aware of the possibility of serious complications?
  • prepared to commit to medical observation for the rest of your life?