1. From the Department of Public Health and Primary Care (K.-T.K., R.L., A.W., N.D.), Institute of Public Health, University of Cambridge School of Clinical Medicine, Cambridge, UK; Academic Department of Biochemistry (M.D., E.F.), Royal Marsden Hospital, London, UK; and MRC Dunn Human Nutrition Unit (S.B.) and MRC Epidemiology Unit (N.W.), Cambridge, UK.