social jet lag
n. Tiredness and disorientation caused by forcing one's body to sleep at unnatural times due to work commitments.
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Long working hours leave more than half of us in a state of permanent "jet lag", according to research.

Those trapped in an office during daylight hours are unable to reset their body clocks.

This means they cannot adapt to early-morning starts or late nights and spend their days in a permanent state of grogginess.

Scientists claim this leaves more than one in two with "social jet lag".
—“Work can be tough,” The Sunday Times, April 01, 2006
Prof Roenneberg said about half the people in his study were disadvantaged by work start and finish times, which he calls "external time" — particularly those whose internal clock meant they should still be asleep when they had to go to work.

"When you travel longitudinally, you suffer jet-lag because, when you arrive, the external time is different from your internal time," he said.

"External time in Germany [and other countries] has never changed since agricultural times and about half the population have to live with an internal and external time difference that is comparable to jet-lag."

And he said the problem was chronic. "Imagine you have to work on Moscow time, but you live in Edinburgh — that's what I'm talking about," he said

Prof Roenneberg said the problem was revealed at the weekends, when people reverted to more natural sleep patterns. Those worst affected by "social jet-lag" slept for about half their time off, simply to recover, he said.
—Ian Johnston, “Late for work again? Just blame it on 'social' jet-lag, say researchers,” The Scotsman, March 30, 2006
2006 (earliest)
This means that well over half the population is effectively suffering from jet lag — even if they catch the bus to work. Roenneberg calls it social jet lag. And it can have some serious consequences. Firstly, you are not alert when you’re jet lagged, so you can’t focus on the job properly. Worse, it can affect your health.

Jet lag and shift work, which can have the same effect, increase the risk of cardiovascular disease, certain cancers and all manner of other health problems.
—Helen Phillips, “Are you…always late?,” The New Scientist, March 24, 2006
You can measure the potential social jet lag in your life: Calculate the average midpoint of your sleep time both on work days and on weekends (or whenever your days off occur). If the difference is an hour or two, then social jet lag isn't likely to be much of a factor in your life; if the difference is more like 7 or 8 hours or more, then you can expect to feel some symptoms of social jet lag.