1. Department of Nutrition, Harvard School of Public Health, Boston, MA 02115
2. Department of Nutrition, National University of Colombia, Bogotá, Colombia
3. National Institute of Health, Bogotá, Colombia
4. San Rafael Clinic, Bogotá, Colombia
5. Department of Community Health, Warren Alpert Medical School, Brown University, Providence, RI 02903
6. Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115