1. Behavioral Medicine Research Unit, Department of Psychosomatic Medicine and Psychotherapy, Integrated Research and Treatment Center AdiposityDiseases, University of Leipzig Medical Center, Stephanstrasse 9a, 04103 Leipzig, Germany
2. Department of General Surgery, Asklepios Clinic, 22559 Hamburg, Germany
3. Schön Klinik Hamburg Eilbek, Obesity Clinic, 22081 Hamburg, Germany
4. Department of General, Visceral, Transplant, Vascular and Pediatric Surgery, University Hospital, University of Würzburg, 97080 Würzburg, Germany
5. Department of Visceral, Pediatric and Vascular Surgery, Hospital Konstanz, 78464 Konstanz, Germany
6. Department of Surgery, SRH Wald-Klinikum, Adipositas Zentrum, 07548 Gera, Germany
7. Department of Surgery, Clinic for Visceral, Transplantation, Thoracic and Vascular Surgery, University Hospital Leipzig, 04103 Leipzig, Germany