All gastric bands work on the same principle – restriction. The band divides the stomach into a small pouch above (about 5% of the stomach) with the main body of the stomach below.
When the gastric band is tightened, the small pouch above the band acts as the stomach and restricts the amount of food that can be taken in at any one time. In other words the brain is “tricked” into thinking that the whole stomach is full, when in fact only the small pouch is full.
Even a small amount of food can produce a feeling of fullness (satiety) so that overall calorie intake may be 50-60% less than usual, leading to weight loss. As the food is slowly digested in the pouch, it passes through the band stoma (opening) into the normal stomach below.
