Is it possible to only get 4 hours of sleep a night and still work productively?

Novelist Danielle Steel seems to think so.

As a sleep expert, having supported hundreds of sleep deprived clients, the idea that someone can sustain that pattern effectively - work, write, commit things to memory, use their full brain capacity - is very hard to conceive.

Click here to read more in this Guardian article about why it's important to prioritise sleep health and how severe sleep deprivation is 'akin to being drunk'.