If you have at least seven hours of interrupted sleep each night, consider yourself very lucky indeed. Problems with sleep are remarkably widespread.

Many millions of adults and children either don't spend enough time in bed or suffer from sleep disorders, resulting in illness, obesity, depression, mood swings and loss of creativity.

Our guest is Jeff Koyen, Editor-in-Chief of Van Winkle's, a new website "obsessed with sleeping, waking and everything in between. He shares the stories of scientists, artists, travel writers, child-care experts and many others who have a great deal to tell us about how we do - and don't - sleep.