Professor Dr. med. Jürgen Ordemann, former holder of the professorship for Obesity Surgery at the Charité – Universitätsmedizin Berlin and since 2018 Head of the Department of Obesity and Metabolic Surgery, Vivantes Klinikum Berlin-Spandau; Priv.-Doz. Dr. med. Ulf Elbelt, former Senior Physician at the Medical Department of Endocrinology and Metabolic Diseases, Charité - Universitätsmedizin Berlin and since 2019 Senior Physician for Endocrinology at Brandenburg Medical School