The following are excerpts from:
Weight Loss Surgery - Gastric Bypass - Gastroplasty - Lap Band
"The Gastric Bypass surgery is a procedure that reroutes the digestive system causing rapid weight loss. Unfortunately gastric bypass also often leads to nutritional deficiencies that can cause severe health complications.
Another type of weight loss surgery often performed is called gastroplasty. Gastroplasty is similar to gastric bypass because it reroutes digestive system, but it also restricts the amount of food that can be eaten by making the stomach smaller.
Neither of the above can be surgically reversed. Both gastric bypass and gastroplasty require a five to six inch incision and a hospital stay of three to four days. Potential side effects resulting from these types of weight loss surgery include “dumping syndrome” which is a combination of nausea, chest, and abdominal cramps, sweating, and diarrhea. Other risks and complications include malabsorption, vitamin deficiencies, and chronic abdominal pain. These symptoms are often avoided by eliminating foods that are high in sugar and fat from the diet.
Now there is the less invasive weight loss procedure, approved in the U. S. by the FDA in June 2001, called the Laparoscopic Adjustable Gastric Banding Procedure or Lap-Band. The Adjustable Gastric Lap-Band is a hollow band made of sylastic. The band is placed around the upper third portion of the stomach to create a small stomach pouch that initially holds 2 ounces of food, and eventually holds up to 4 to 6 ounces. Creating this restricted stomach space in the upper portion of the stomach causes a longer lasting feeling of fullness because the nerves that signal the brain when you're full are located in the upper area of the stomach. The band further works by slowly allowing the food you eat to be released into the lower portion of the stomach for digestion."
You can read the rest of the article. Any deeper questions? You should contact your own doctor.