1. Health Behaviour Research Centre (J.W., S.C.), Department of Epidemiology and Public Health, University College London, London WC1E 6BT, United Kingdom
2. Social, Genetic, and Developmental Psychiatry Centre (C.M.A.H., R.P.), Institute of Psychiatry, King’s College London, London SE5 8AF, United Kingdom
3. University of Cambridge Metabolic Research Laboratories (I.S.F., S.O.), Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge CB2 2QQ, United Kingdom