Laparoscopic Roux-en-Y Gastric Bypass (LRYGB)
This procedure is currently the standard by which other weight loss operations are measured. The term "gastric" simply means something that involves the stomach. When combined with lifestyle and behavioral changes, "gastric bypass" leads to safe, significant and sustained weight loss by restricting the amount of food you can consume and the calories your body can absorb.
Right now, when the food you eat reaches the sack-like lower portion of your stomach it is released into the upper section of the small intestine, called the duodenum. Here, digestive juices from the stomach, pancreas, liver and gallbladder combine to aid digestion and absorption of calories and nutrients from the food.
During gastric bypass surgery, the top portion of your stomach is separated from the lower portion to create a small pouch. The lower portion of your stomach is closed, but will continue to create important chemicals for digestion and release them into the duodenum of the small intestine.
Next, the middle portion of your small intestine, called the jejunum, is divided; one end is then brought up and connected directly to the small stomach pouch to create a two to five foot length of intestine called a Roux limb. This "limb" enables food entering the small stomach to bypass part of the small intestine so that fewer calories and nutrients are absorbed.
The other end of the divided small intestine, which comes down from the lower portion of your stomach, is then connected to the Roux limb about two to five feet downstream of the small stomach pouch. This creates a "y-shaped" connection to the small intestine and allows the digestive juices from the stomach, pancreas, liver and gallbladder to mix with the food coming from the small stomach pouch.
How You Lose Weight
Gastric bypass surgery helps you lose weight in three ways.
- You will consume fewer calories. That's because the small stomach pouch created during surgery will fill quickly, restricting the amount of food you eat. You'll feel full more quickly and, therefore, consume less food and fewer calories.
- Your body will absorb fewer calories because the food you eat will bypass part of the small intestine. Instead, food that fills the small stomach pouch will now enter the Roux limb, a redirected section of the small intestine (described further in the surgery section above). The food travels two to five feet along the Roux limb before being mixed with juices from the stomach, pancreas, liver and gallbladder. It's at this point that the body digests and absorbs the food's nutrients. Your body's new digestive process results in "malabsorption" so that fewer of the calories you consume during a small, healthy meal will actually be absorbed into the body.
- Your eating behavior will change. After surgery, you'll quickly learn that foods containing large amounts of sugar will tend to cause abdominal cramping, nausea, diarrhea and other symptoms known as "dumping syndrome." As a result you'll learn to make healthier food choices. This "behavioral modification" can play an important role in helping you to increase and maintain your weight loss.
After LRYGB surgery, patients experience safe, significant and sustained weight loss while adhering to a life-long regimen of sensible exercise with appropriate dietary intake, plus vitamin and mineral supplements, and consistent follow-up.