1. Department of Nutrition, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, U.S.A.
2. Department of Cardiology, University Medical Center Groningen, P.O. Box 30001, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
3. Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, U.S.A.
4. Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, U.S.A.
5. Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, 900 Commonwealth Avenue, Boston, MA 02115, U.S.A.