I cant find the episode now, but a few years ago an episode CBC's science show Quirks and Quarks interviewed a researcher that found being bilingual seemed to delay the onset of dementia by a couple of years. Although it doesnt sound like much, from a public policy pov, its pretty significant when you look at what that can mean for quality of life as well as costs for our public health system.

Unfortunately, you can't take an 50-something english only American and tell him to "go learn Italian", for health. It's hard enough to make people eat less, exercise, or quit smoking - picking up new language without another motivation than "for health" is going to be even harder.

Most schools introduce more languages today, no ? And I guess there is no motivation to keep language skills active beyond school, so any skill here will likely atrophy like me French :(

its been a while since I heard the doc, but I dont think it was so much a "lets all learn another language" as opposed to looking what might be happening in the brain to cause such an odd disparity in how the disease manifests itself.

I wonder if knowing one language delays the onset of dementia by X. then being bilingual delays dementia by X/2. then being trilingual delays dementia by X/3. and so on ...