**4.1 Bariatric pacing**

As early as 1980, the vagal system gained attention as a possible target in obesity treatment. Patients with peptic ulcer disease temporarily lost weight after truncal vagotomy [41, 42]. Only 10–20% of the vagal nerve fibers are composed of efferent fibers that control stomach activity, whereas the remaining 80–90% consist of afferent fibers that send signals regulating satiety and satiation [43]. With this in mind, application of electrical current to the stomach vagus nerve alters gastric myoelectrical activity. While the exact mechanism of action remains to be elucidated, bariatric pacing poses a new frontier in the treatment of severe obesity.
