WASHINGTON– Permission to sleep in.

That’s what researchers at the University of Pennsylvania Perelman School of Medicine are suggesting that employers might consider. Their American Time Use Survey of close to 125 thousand people found a link between early start times and lack of Z’s.

Unfortunately, according to the researchers, that can translate into bad health and productivity over all.

So who is getting the least amount of sleep? Those workers who start earlier in the day and ended work later in the night — and they have a long commute to get there. Every hour later that person started to work (or if a student, went to class) sleep time increased by approximately 20 minutes. Those working multiple jobs were 61 percent more likely to be short sleepers. But self-employed respondents with more flexible work times were less likely to be short sleepers on weekdays.

And probably no surprise — average sleep time was higher during the economic crisis years when there were lower employment rates.

“The evidence that time spent working was the most prominent sleep thief was overwhelming,” lead author Dr. Mathias Basner, assistant professor of sleep and chronobiology in Psychiatry at the school, said at the University of Pennsylvania website.

“It was evident across all sociodemographic strata and no matter how we approached the question.”

The American Academy of Sleep recommends 7 to 9 hours as essential to our physical and mental well-being.

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