1. Centre for Obesity Research, University College London , London WC1E 6JF , UK
2. Bariatric Centre for Weight Management and Metabolic Surgery, University College London Hospitals NHS Trust , London NW1 2PG , UK
3. National Institute for Health Research, UCLH Biomedical Research Centre , London W1T 7DN , UK
4. Division of Bone Diseases, Geneva University Hospitals and Faculty of Medicine, University of Geneva , 1211 Geneva , Switzerland
5. Diabetes Centre, Faculty of Medicine, University of Geneva , 1211 Geneva , Switzerland
6. The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London , London WC1E 6HX , UK
7. Division of Nutrition, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University , Bangkok 10700 , Thailand
8. Bariatric Surgery Department, Homerton University Hospital NHS Trust , London E9 6SR , UK
9. NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London , London WC1N 3BG , UK
10. Service of Endocrinology, Diabetes, Nutrition and Therapeutic Education, Department of Medicine, Geneva University Hospitals , 1211 Geneva , Switzerland
11. Department of Surgery, Whittington Health NHS Trust , London N19 5NF , UK
12. University College London , London WC1E 6BT , UK