Thorkild I A Sørensen achieved his M.D. from University of Copenhagen in 1971 and got the Dr Med Sci degree in 1983. He worked as clinician in various hospitals in Copenhagen, lastly as chief physician in internal medicine and liver disease, until 1989, when he received a 5-year MRC professorship in clinical epidemiology. In 1993 he became Director of the hospital-based Institute of Preventive Medicine, and in 1994 chief physician of clinical epidemiology at the institute and clinical professor of clinical epidemiology at the Department of Public Health of the Faculty of Health Sciences, University of Copenhagen. Since 2011, he has also been professor of metabolic epidemiology at the Novo Nordisk Foundation Center for Basic Metabolic Research at the Faculty of Health and Medical Sciences, University of Copenhagen. He has published hundreds of scientific papers, during the recent years mostly about epidemiology of obesity and related conditions.