Getting Enough Sleep Is Non-Negotiable

Death from overwork has its own word in Japanese (karo­shi), in Chinese (guolaosi), and in Korean (gwarosa). No such word exists in English, but the casualties are all around us. And though this is an extreme example of the consequences of not getting enough sleep, sleep deprivation has become an epidemic....
http://www.alternet.org/books/arianna-huffington-sleep-deprivation-book