Sleep: A user's guide

It’s as essential to survival as food and drink, yet many of us struggle to get enough of it. So how do you know how much sleep is enough, and whether it’s good enough for you to reap the benefits? Can you get by with less? How can you get to sleep more easily – failing that, can you nap your way to success instead? In this guide to your unconscious hours, we answer the sleep questions keeping you up at night.