More than half of the European population is overweight [body mass index (BMI) >25 and <30 kg/m2] and up to 30% is obese (BMI>30 kg/m2). Overweight and obesity are associated with many comorbidities such as: insulin resistance/type 2 diabetes, dyslipidemia, hypertension, cholelithiasis, cancer, liver steatosis, gastroesophageal reflux, obstructive sleep apnea, degenerative joint disease, gout, and others. It has been demonstrated that weight reduction in short term (1–3 years) leads to a decline in insulin resistance, a better metabolic regulation in patients with diabetes mellitus, a reduction in blood pressure, and a less atherogenic lipid profile. Several investigations have reported impairments in specific domains of Quality of Life (QoL) in persons with extreme obesity. More specifically, these studies have suggested that both health-related (HR-QoL) and weight-related quality of life (WR-QoL) are dramatically impacted by extreme obesity. Encouragingly, both health-related and weight-related quality of life appear to improve following bariatric surgery. Some studies indicate that weight reduction in the severely obese is accompanied by improvements in Health Related -Quality of Life and that a dose-response relationship exists between the magnitude of weight loss and HR-QoL benefits. At present, surgical intervention is the only treatment yielding a more durable weight loss and an improvements in health status and in HR-QoL. In severely obese a Study after weight loss surgery showed over 10 years that long-lasting weight reduction in the severely obese has a general long-standing positive outcome on HR-QoL.