The ex-CEO of Evernote says Silicon Valley's favorite fasting diet has changed his life -- here's his routine

Phil Libin, the ex-CEO of Evernote, doesn't eat for two to eight days in a row. He subscribes to an increasingly popular diet called intermittent fasting, which has a host of benefits backed by science. Techexecutives say fasting gives them a mental edgein Silicon Valley. Phil Libin, who helped create the popular productivity app Evernote in 2007 and ledthe company as CEO until 2015,was melancholy for a long time. His work didn't excite him. Eventually he pinpointed the source. "It was the carbs...