For many people suffering from severe obesity, a simple diet and exercise routine is not enough to control their weight problems. Some have opted for surgical treatment - namely gastric bypass, or bariatric, surgery - to aid in weight reduction and secure a healthier future. The technique was originally considered upon observation of previous cancer or ulcer-related operations, in which the removal of portions of the small intestine or stomach often resulted in post-surgery weight loss for the patient [1]. Pounds would be shed as the patient experienced a decrease in appetite and intestinal absorption. Doctors first experimented with the intestinal bypass as a means for weight loss around forty years ago; large amounts of food could be eaten, but only a small percentage would be digested or properly absorbed. The surgery indirectly caused deleterious and sometimes fatal side effects, as patients lost many essential nutrients [1]. The surgical procedure has been modified since then to minimize such damage.

Gastrointestinal surgery can promote weight loss in two ways: a "restrictive operation" closes off parts of the stomach so that it can hold only a small amount of food, causing the patient to feel satiated more quickly; a "malabsorptive operation" reduces stomach size and allows the bypassing of parts of the small intestine, preventing some calorie and nutrient absorption [1]. The Roux-en-Y (RGB) is the most common and successful type of gastric bypass surgery, and it involves a three-step process (See Figure 1) [2]. First, a small gastric pouch is created from the patient's original stomach and separated from the remainder of the stomach, thus restricting the stomach's capacity [2]. The small intestine is divided into three segments: the duodenum, jejunum, and ileum. In the second step of the surgery, the jejunum is divided at a point approximately fifty centimeters past its origin, and then connected to the gastric pouch created in step 1. This portion of the jejunum is called the Roux limb. Lastly, the Roux limb is reconnected to the duodenum and the first fifty centimeters of the jejunum. In the duodenum, essential secretions from the remainder of the stomach combine with pancreatic and hepatic juices to digest fats, proteins, and complex carbohydrates. Without this step involving reconnection to the duodenum, digestion could not take place [2].

This surgical procedure is not a suitable means of weight control for all overweight people. It is usually recommended for people with a body mass index (BMI) over 40 - about eighty pounds overweight for women and one hundred pounds overweight for men (See Figure 2) [1]. Other candidates for the surgery are people with a BMI of 35-40 who have life-threatening health problems related to obesity, such as type 2 diabetes, heart disease, or severe sleep apnea. Those who experience physical problems as a result of obesity while walking or working may also consult a doctor to see if bariatric surgery is an option for them [1].

Weight loss is quick and continuous following a successful surgery. Most patients continue losing weight 18-24 months after the surgery, and may only gain back in their lifetime 5-10% of the weight they lost. Thus the results of the procedure tend to be long-term [1]. Many obesity-related health conditions are improved following surgery, including decreased sleep apnea and lower blood sugar levels for those with diabetes [1]. However, patients should beware of some obvious risks. With significant weight loss the chance of developing gallstones, or clumps of cholesterol, increases. This may be prevented by taking supplemental bile salts for six months after the surgery [1]. About 30% of the patients suffer from post-surgery nutritional deficiencies and may develop anemia or osteoporosis, among other diseases [1]. Patients must compensate for the decreased absorption in the small bowel by having enough vitamins and minerals in their diet [2]. Fertile women should wait until their weight is stable before pregnancy, so that the fetus does not acquire any nutritional deficiencies [1]. Post-surgery complications occur in 10-20% of the patients, although laparoscopic techniques have greatly increased the precision of the operation, creating less tissue damage [1]. While most patients fully recover and return to their daily routine ten to twelve days after the surgery, all patients must remember to adhere to a permanent regimen of chewing more, eating smaller, vitamin-enriched meals, and visiting the doctor regularly for follow-up examinations [2]. Gastric bypass surgery is an excellent tool for those ready to lose weight, but also prepared to make a lifetime commitment to their physical health.