General Surgery is the specialty that treats surgically the pathologies of the digestive system, the gastrointestinal tract and the hepato-bilio-pancreatic system, as well as the endocrine system. It is responsible for endocrine surgery and obesity. Likewise, it includes the repair of the hernial effects of the abdominal wall. The Morbid Obesity Unit deals with morbid obesity, or severe obesity. Obesity is defined by the World Health Organization as the excessive accumulation of energy in the form of fat, which has adverse effects on health and the duration of life. The evaluation of excess weight is based on the body mass index, a tool that correlates weight with height.