1. Department of Internal and Vascular MedicineAmsterdam University Medical Centers Amsterdam the Netherlands
2. Department of Endocrinology and MetabolismAmsterdam University Medical Centers Amsterdam the Netherlands
3. Department of Nutrition, Exercise and SportsUniversity of Copenhagen Copenhagen Denmark
4. Endocrine Laboratory, Department of Clinical ChemistryAmsterdam University Medical Centers Amsterdam the Netherlands
5. Department of Laboratory Medicine, University of GroningenUniversity Medical Center Groningen the Netherlands