To celebrate World Sleep Day, here's our science-based guide to getting the best slumber you can – from varying sleep with the seasons to taking inspiration from the past.

It's a typical weekday morning, and you're just beginning to stir in bed. There's light streaking through the windows, while the many chirps and caws of birds announce that it's probably time to get up… but surely that can't be right? Cue the familiar feeling of dread, as you remember a night filled with restless, low-quality sleep.

Across the world, people are struggling with insufficient sleep. In the US alone, it's been estimated that........

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