[1] Univ Perugia, Sch Med, Inst Gerontol & Geriatr, Dept Clin & Expt Med,Policlin Monteluce, I-06122 Perugia, Italy
[2] Tufts Univ, Human Nutr Res Ctr Aging, Boston, MA 02111 USA
[3] Univ Barcelona, Dept Nutr & Food Sci, CeRTA, Barcelona, Spain
[4] Univ G DAnnunzio, Dept Med & Aging, Lab Clin Epidemiol, Geriatr Unit, Chieti, Italy
[5] INRCA Florence, Lab Clin Epidemiol, Florence, Italy
[6] NIA, NIH, Longitudinal Studies Sect, Clin Res Branch, Baltimore, MD 21224 USA