Bariatric Surgery and Weight Loss

Bariatric surgery is being used more frequently, but important lifestyle changes must still be made.
Bariatric Surgery and Weight Loss

Although bariatric surgery is being done more frequently — the number of surgeries has increased to over 250,000 surgeries in 2008 compared to just 18,000 a decade ago1—it continues to be reserved for the severely obese.

Types of Surgery
There are actually two basic types of bariatric surgeries: restrictive and combined restrictive/malabsorptive. Restrictive operations (e.g. LAP-BAND) work by using bands or staples to restrict the stomach size, thereby reducing the amount of food that can be comfortably eaten. Combined restrictive/malabsorptive operations (e.g., Roux–en-Y gastric bypass) work by restricting the stomach to limit food intake and rerouting the small intestine to reduce the amount of calories and nutrients that are absorbed into the body.

To qualify for the combined restrictive/malabsorptive operation, a person must have a Body Mass Index (BMI) of at least 40 kg/m2 or be 100 pounds overweight. Those with a BMI between 35 and 39.9 and with a serious health problem such as Type 2 diabetes, heart disease, or high blood pressure may also be considered for surgery. In December 2010, the FDA approved the LAP-BAND restrictive operation for obese patients with a BMI of at least 35 or a BMI of at least 30 with one or more comorbid conditions.

Results of Surgery
Patients lose an average of 50% of the excess weight with all bariatric procedures and this is usually achieved 12-18 months after the surgery2 and regain 10-15% over three to ten years.3 The combined surgeries appear to be more effective at achieving weight loss but the restrictive operation appears to have less severe long-term complications.4 With the weight loss that comes from the surgery, improvements in several health problems such as diabetes, hyperlipidemia, hypertension and sleep apnea have been found.

Risks and Side Effects
Bariatric surgery is a major operation and therefore carries health risks and complications. The death rate from bariatric surgery is less than 0.3%; combined surgeries carry greater risk than restrictive surgeries.5 Reported side effects include nausea, abdominal pain, vomiting, and particularly with combined surgeries, "dumping syndrome" and nutritional deficiencies.

Bariatric Surgery and Lifestyle Modification
Bariatric surgery requires making major changes in eating behaviors, with the type of changes needed as well as the need for dietary supplements depending on the type of surgery. Long-term weight-loss success also requires lifestyle modification.

The Weight Watchers Approach:

Lifestyle modification is the cornerstone of the Weight Watchers approach– making wise food choices, being physically active, developing positive behavioral skills, and being in a supportive environment. These four pillars are especially important for those who have undergone bariatric surgery.

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1 American Society for Metabolic & Bariatric Surgery

2 Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, Schoelles K. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004 Oct 13;292(14):1724-37.

3 Poirier P, Cornier MA, Mazzone T, Stiles S, Cummings S, Klein S, McCullough PA, Ren Fielding C, Franklin BA; on behalf of the American Heart Association Obesity Committee of the Council on Nutrition; Physical Activity, and Metabolism. Bariatric Surgery and Cardiovascular Risk Factors: A Scientific Statement From the American Heart Association. Circulation. 2011 Apr 19;123(15):1683-1701.

4 Franco JV, Ruiz PA, Palermo M, Gagner M. A review of studies comparing three laparoscopic procedures in bariatric surgery: sleeve gastrectomy, Roux-en-Y gastric bypass and adjustable gastric banding. Obes Surg. 2011 Apr 1. [Epub ahead of print].

5 Longitudinal Assessment of Bariatric Surgery (LABS) Consortium; Flum DR, Belle SH, King WC, Wahed AS, Berk P, Chapman W, Pories W, Courcoulas A, McCloskey C, Mitchell J, Patterson E, Pomp A, Staten MA, Yanovski SZ, Thirlby R, Wolfe B. Perioperative safety in the longitudinal assessment of bariatric surgery. N Engl J Med. 2009; 361:445– 454.

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