The lap-band system works by wrapping a silicon band around the top portion of the stomach. All the food then has to squeeze through the band. This bottleneck causes the patient to feel full with less food, and to not feel hungry.The reason behind the success of the lap-band has a great deal to do with the fact that it is adjustable. The band is connected by tubing to a port, which is placed just below the skin in the front of the abdomen. By injecting saline into the port, which can usually be done in the office, the band can be tightened or loosened as determined by how the patient feels.