David A. Snowdon is an American epidemiologist. His research interests include antioxidants and aging, and the neuropathology of Alzheimer’s disease. Director of the Nun Study, a longitudinal study of aging and Alzheimer’s disease, he is following 678 members of the School Sisters of Notre Dame aged over 75 years. His book on the Nun study, “Aging with Grace: What the Nun Study Teaches Us about Leading Longer, Healthier, and More Meaningful Lives”, won a Christopher Award in 2002.
Source - Wikipedia http://en.wikipedia.org/wiki/David_Snowdon