[1] Karolinska Inst, Inst Environm Med, Unit Nutr Epidemiol, Box 210, S-17177 Stockholm, Sweden
[2] Univ Cambridge, Sch Clin Med, MRC, Epidemiol Unit,Inst Metab Sci, Box 285,Cambridge Biomed Campus, Cambridge CB2 0QQ, England
[3] Karolinska Inst, Publ Hlth Sci, Tomtebodavagen 18A,Widerstromska Huset, S-17177 Stockholm, Sweden