It is 10:40pm. Everything that had to happen today has happened. The dishwasher is humming, the school bags are by the door, tomorrow’s outfit is already hanging up, and for the first time since breakfast nobody is asking you for anything.
And you are not going to bed.
You know you should. You have known it for an hour. But going to bed now means the day ends without ever having contained anything that was yours, and tomorrow starts the same way. So you stay. You watch something, or scroll something, or just sit in a quiet room. It is not restful, exactly. It is not even especially enjoyable. But it is yours, and it is the only part of the day that is.
There is a name for this, and it did not come from a wellness app. It’s called revenge bedtime procrastination.
Where the phrase came from
In Chinese it is 報復性熬夜 — bàofùxìng áoyè — which translates roughly as retaliatory staying up late. It emerged in China in the late 2010s, out of a working culture known as 996: nine in the morning to nine at night, six days a week.
The earliest use anyone has traced appears on the blog of a worker in Guangdong province. He wrote that during the working day he belonged to someone else, and only found himself again after getting home. He knew the lost sleep was doing him harm. He also thought it bought him something worth having.
The phrase reached English in the summer of 2020, when the journalist Daphne K. Lee described it as what happens when people who have little control over their daytime lives refuse to sleep early in order to reclaim a few hours of freedom.
When I first came across it, it felt less like learning a new concept and more like finally having words for something I’d been doing for years. Not because I don’t value sleep, but because the quiet after everyone else has gone to bed can feel like the only part of the day that hasn’t already been spoken for.
What is striking about the origin is what is absent from it. Nobody involved was talking about willpower. They were describing a rational response to a day that had no room in it. The academic literature had already named something similar — bedtime procrastination, defined in 2014 as failing to go to bed at the time you intended when nothing external is stopping you — but the borrowed Chinese phrase carried the part the definition missed. Not a failure. A retaliation.
Almost every piece of advice written about this since has ignored that distinction, and prescribed an earlier bedtime.
What the hour actually costs
Here is the part that is harder to argue with.
In July 2026, researchers at Columbia University published a study in the Annals of Internal Medicine that did something unusually useful: instead of observing people who already sleep badly, they took 95 adults who normally slept seven to eight hours a night and asked them to delay their bedtime by ninety minutes for six weeks. The same people also completed six weeks of normal sleep, so each person acted as their own comparison.
In practice, the participants lost an average of 78 minutes a night. Not a bad week. Not an all-nighter. An hour and a bit — the shape of an ordinary evening that ran on longer than it should have, repeated for six weeks.
Over that period, their weight rose by an average of just under half a kilo, and their waists by around half a centimetre. Their sedentary time increased by about 17 minutes a day, and in men and postmenopausal women by nearly thirty. Their moderate and vigorous activity did not change at all — the extra waking hours did not become extra movement. They became extra sitting.
Two things are worth being precise about, because most coverage of this study was not.
The first is that body composition did not measurably change. Weight went up. The proportion of fat and muscle did not. Six weeks is not long, and what the researchers observed was the beginning of something rather than the whole of it.
The second is that these were people already at raised cardiometabolic risk, and there were only 95 of them. It is a small study of a specific group. But because participants were randomly assigned to each phase and compared against themselves, it can say something most sleep research cannot: this looks like cause, not just company.
The research team estimates that around 30% of adults live this pattern permanently.
Why the usual advice fails
If you have read anything about sleep in the last decade, you know the list. Consistent bedtime. No screens. Cool, dark room. Nothing after midday with caffeine in it. And somewhere near the end, magnesium — which, as I’ve written before, has a thinner evidence base than the marketing suggests, and in any case cannot solve a problem that was never chemical.
None of it is wrong. All of it assumes the problem is that you do not know what to do.
But you are not staying up because you are unaware that sleep matters. You are staying up because the alternative is a day with no unclaimed time in it, and no amount of information about melatonin changes that arithmetic. Advice that begins go to bed earlier is asking you to give up the only hour of the day nobody else has a claim on, in exchange for a benefit you cannot feel tomorrow morning.
Most people, sensibly, decline.
The bit that changes the arithmetic
Which brings us to the finding that makes this article worth writing.
In 2024, researchers analysed more than ten million hours of accelerometer data from nearly 61,000 people in the UK Biobank — objective measurements, not a questionnaire about how well anyone thought they slept. They compared two things: how much people slept, and how consistently they slept at the same times.
Consistency won.
People with more regular sleep timing had substantially lower mortality risk than the least regular group, and — this is the part that matters — regularity predicted risk more strongly than duration did. This is observational research, so it shows association rather than proof, and it cannot rule out that people already unwell sleep more erratically. But the authors drew a practical conclusion from it that is worth quoting almost directly: asking people to keep similar sleep times from day to day may be a more achievable target than asking them to spend more of the day asleep.
Read that again in the context of your evening.
It does not say you have to surrender the hour. It says that an hour taken at roughly the same time every night is a different proposition from an hour taken at 11pm on Monday, 1am on Wednesday, and not at all on Thursday because you fell asleep on the sofa.
The irregularity may be doing more damage than the lateness.
What that looks like on an ordinary Tuesday
Not a routine. A single adjustment.
Decide what time your evening actually ends — the real time, the one you would defend, not the aspirational one. If that is 11:30pm, let it be 11:30pm. Then hold it on the nights you can, including the nights when the hour was good and you would rather keep going.
That is it. No app, no supplement, no reordering of the household.
And on the evenings when something is genuinely worth staying up for — a friend, a film, a conversation that finally arrived — stay up. A late night you chose is not the same as an evening that dissolved. The research is about the pattern, not the exception.
The honest version
Sleep debt does not get built by dramatic nights. It gets built in ordinary instalments, on evenings that were never quite worth it, in a house that has finally gone quiet.
The answer is not to want the hour less. The hour is doing something real — it is the only part of the day that belongs to you, and that is a legitimate thing to need.
You don’t have to give up the hour. You have to keep it at the same time.
A good life isn’t built by squeezing every possible minute out of the day. It’s built by protecting enough of them that you still recognise yourself in it.
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