1. Department of Endocrinology, Morbid Obesity, and Preventive Medicine, Oslo University Hospital, Oslo, Norway2Institute of Clinical Medicine, University of Oslo, Oslo, Norway
2. Department of Gastrointestinal Surgery, Oslo University Hospital, Oslo, Norway
3. Department of Gastrosurgical Research and Education, Department of Surgery, Sahlgrenska University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden
4. Department of Endocrinology, Morbid Obesity, and Preventive Medicine, Oslo University Hospital, Oslo, Norway
5. Unit of Biostatistics and Epidemiology, Oslo University Hospital, Oslo, Norway
6. Department of Gastrosurgical Research and Education, Department of Surgery, Sahlgrenska University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden6Diabetes Complications Research Centre, Conway Institute, University College Dublin, Dubl
7. Nutritional Laboratory, Biochemical Department, Oslo University Hospital, Oslo, Norway
8. Department of Endocrinology, Morbid Obesity, and Preventive Medicine, Oslo University Hospital, Oslo, Norway3Department of Gastrointestinal Surgery, Oslo University Hospital, Oslo, Norway