The Globe and Mail recently had an article on the benefits of reading and good literacy to your health (PDF). This is probably not a huge surprise but lines like “While we obsess about our weight, blood pressure and cholesterol levels, the single best predictor of good health and longevity is probably literacy.” are pretty big statements to make. (I'd have guessed that the single best predictor of longevity might have to do with healthy eating and exercise.)
(via one of our branch librarians who in turn, got it from a librarian at RPL)