Who Broke Bedtime?
DR SHAADY HARRISON | 3 minutes
Nobody teaches a human how to fall asleep.
The instructions were written long before we arrived, and every single one of us was born already holding them.
Evolution spent millions of years perfecting the transition into sleep.
Modern life managed to screw it up in a few decades.
Night isn’t Night Anymore
We know more about sleep than ever.
We’ve devoted entire industries to the pursuit of better rest, inventing everything from cutting-edge smart rings to AI-powered sleep trackers in an attempt to wake up fully recovered.
And yet, generally speaking, sleep has become a bit of a disaster.
Sleep is governed by two ancient systems. One tracks how long we’ve been awake, while the other follows the rhythm of the day, using light as its strongest signal.
For hundreds of thousands of years, these systems worked in perfect harmony.
Then we built a world that started giving them the wrong instructions.
Over the last century, a handful of brilliant inventions have erased almost every cue that used to signal nighttime. The lights stay on, the world keeps talking and a constant stream of content keeps the evening alive and full of unfinished business.
At 9pm nothing around us seems to be clocking off.
So funnily enough, our brains don’t want to either.
We Weren’t Supposed to Decide
Our ancestors didn’t have to consciously engineer the conditions for bedtime.
The environment did most of the work for them; sleep was the natural next step in a day simply coming to an end. This looked far from some sort of serene prehistoric wellness retreat – night could be cold, boring and pretty uncomfortable.
But it was unmistakably different from daytime.
The brain received a steady stream of evidence that the world was winding down, so the body took the hint and acted accordingly.
Fast forward a few thousand years and bedtime has changed from an environmental event to a choice we actively have to make.
So in a world where night no longer feels like night, how can we bring bedtime back?
Context Is Everything
The same person eats differently depending on plate size, walks differently depending on city design and behaves differently depending on who they’re surrounded by.
Our environment shapes our decisions long before we realise we’re making them.
We’ve spent centuries trying to extend the day beyond sunset, and for good reason too – modern life has built a world where almost nothing has to wait until morning.
But we may have overshot slightly when every shop, office, and entertainment system became available from underneath a duvet.
Our nervous system expects the evening to look like a gradual descent into darkness, stillness and calm.
A final hour that actually feels different – quieter spaces, less stimulation and a slower pace – tells the brain what the sunset used to, making it far easier to draw a line in the sand between being on and off.
Night isn’t supposed to be a lower-lit version of the day.
When the evening genuinely looks like an ending, the body recognises the signal, relaxes, and starts the long-rehearsed process of shutting down.
The brain hasn’t forgotten how to switch off - it's just waiting for the rest of the room to do it too.
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Evolutionary mismatch, chronic disease, and the human body
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About The Author
Shaady Harrison is a British medical doctor, writer and private advisor specialising in the intersection of psychology, calm and performance.