1. From the Endocrine Research Unit, Mayo Clinic, Rochester, MN (YDT, CK, MVK, SBV, EW, and MDJ); the Department of Human Physiology, Pennington Biomedical Research Center, Baton Rouge, LA (YDT and EW); and the Postgraduate Program in Epidemiology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil (EW)