1. Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
2. Norwegian Institute of Public Health, Oslo, Norway
3. Oslo Centre for Biostatistics and Epidemiology, Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo Faculty of Medicine, Oslo, Norway.
4. Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, and The Lipid Clinic, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway