1. Center for Obesity Northern Netherlands, Department of Bariatric and Metabolic Surgery, Medical Center Leeuwarden , Leeuwarden , The Netherlands
2. Department of Surgery, Medical Center Leeuwarden , Leeuwarden , The Netherlands
3. Postgraduate School of Medicine, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
4. Department of Endocrinology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands