What does Gastric Bypass Involve?
The gastric bypass involves stapling and dividing the stomach to make a new, smaller stomach about the size of an egg. A piece of the intestine (the "Roux" limb) is then connected to the new smaller stomach for food to pass through and is then reconnected to the lower intestine to form a Y.
The smaller stomach helps you feel satisfied, even full, after consuming a very small amount of food. This food then passes through the Roux limb and meets the digestive fluids at the Y connection. The remainder of your stomach still produces these digestive fluids to meet the food at the Y.
Very little digestion occurs until the food and digestive fluids meet. In other words, you not only eat less, but you also don't fully absorb all the calories you eat. This is called malabsorption. Some malabsorption is OK, but too much can have negative effects on your health.
The bypass we perform at Jefferson only bypasses approximately one-third of the intestinal tract, leaving the last two-thirds to be the "common limb," which absorbs food relatively normally. The amount of malabsorption caused by the bypass that we perform is minimal and easily overcome from a nutritional standpoint by taking a few over-the-counter supplements every day.
By eating less and not fully absorbing calories in food, most people will generally lose 60 to 70 percent of their excess body weight with this procedure. Most weight loss occurs in the first one and a half years. At that point, your weight will stabilize and the weight loss from the gastric bypass is done. The gastric bypass will, however, help you to continue to feel satisfied on very little food, and you can maintain this healthy weight for the rest of your life.