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 1, 2006
"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
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


