Vitamin D and Insulin Action and Secretion Serum Vitamin D concentration Does Not Predict Insulin Action or Secretion in European Subjects with the Metabolic Syndrome Running title: Vitamin D and Insulin Action and Secretion

Department of Clinical Endocrinology, Oslo University Hospital Aker and Faculty of Medicine, University of Oslo, Norway Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Norway Nutrigenomics Research Group, UCD Conway Institute, University College Dublin, Republic of Ireland Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, UK Institute of Cardiovascular and Metabolic Research, University of Reading, UK INSERM, 476 Human Nutrition and Lipids, University Méditerranée Aix-Marseille 2, Faculty of Medicine, France Department of Human Biology, NUTRIM, School for Nutrition, Toxicology and Metabolism, Maastricht University, The Netherlands Lipids and Atherosclerosis Research Unit, Reina Sofía University Hospital, Maimonides Institute for Biomedical Research at Cordoba (IMIBIC), University of Cordoba, Ciber Phyisiopatology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, Spain Department of Clinical Biochemistry, Jagiellonian University Medical College, Krakow, Poland Department of Public Health and Caring Sciences/Clinical Nutrition and Metabolism, Uppsala University, Sweden