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 cardio-vascular disease, high blood pressure, high cholesterol and diabetes.

But there may be hope for the severely, or morbidly, obese, defined as 100 pounds or more overweight: a procedure 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.

What is bariatric surgery?

Bariatric surgery promotes weight loss by restricting food intake in the stomach by rerouting food to reduce caloric intake (malabsorptive surgery) or by decreasing the stomach's size (restrictive surgery).

Malabsorptive surgery. This type of operation combines stomach restriction with a partial bypass of the small intestine and is the most common and successful type of weight-loss surgery. Yet, it is the most complex. 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.

Malabsorptive surgeries include:

• Roux-en-Y gastric bypass. RGB is the most common and successful malabsorptive 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.

Restrictive surgery. Less common, and usually considered more risky, is restrictive surgery, sometimes generally referred to as gastroplasty. The two most popular types of surgery are vertical banded gastroplasty (VBG) and adjustable gastric banding (AGB). They restrict the amount of food you can eat without interrupting normal digestion by creating a small pouch with staples (VBG) or a band (AGB) at the top of the stomach to hold food. The pouch empties very slowly, creating an early feeling of fullness.

Life after surgery

After both types of surgeries, 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, depending on the procedure used. Malabsorptive surgery, especially BPD, comes with a risk of nutritional deficiencies. Patients must take supplements for the rest of their lives to counteract the loss of nutrients. They 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 their lives.