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We spend a third of our lives either sleeping… or trying to get to sleep. But in the world of 24/7 living and artificial light, our sleep is increasingly under threat.

Many of us don’t get the recommended seven to nine hours we need each night and struggle to get up in the mornings – especially on work days. But it isn’t only our quantity of sleep that’s affected. Since the discovery that light (particularly blue light, emanating from devices like smartphones) can affect our biological clocks, evidence has been building that exposure to even low levels of light in the evening or at the night is disrupting our sleep quality, as well.

So what would happen if we turned off the lights? Would it improve our sleep or have other benefits? And how easy would this be to achieve in a modern city?

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One recent winter, I decided to find out. Working with sleep researchers Derk-Jan Dijk and Nayantara Santhi at the University of Surrey, I designed a programme to go cold-turkey on artificial light after dark, and to try to maximise exposure to natural light during the day – all while juggling an office job and busy family life in urban Bristol.

The discoveries I've made have revolutionised my attitude to light ­­­– and how I live my life during the night and day. I now make simple, daily choices that can transform how I sleep, how I feel and perhaps even my cognitive abilities. Could you be doing the same?