Our new favorite scientist: The best time to start your workday is 10 a.m.

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Scientist Paul Kelley has some sage advice for employers: Start your workday at 10 a.m. Anything earlier is bad news for everyone.

Speaking at the British Science Festival this week, the Oxford University researcher explained that a 9 a.m. to 5 p.m. day makes sense for us when our body's circadian rhythm is aligned with that schedule, but that doesn't happen until we turn 55. From age 10 to 55, our internal clock is all over the place.


The ideal school start time for a 10 year old, he says, is 8:30 a.m. But 16 year olds should start at 10 a.m., and 18 year-olds 11 a.m., to maximize their alertness and make sure they aren't sleep deprived. After that, workers should stick to a 10 a.m. schedule for a healthy, productive lifestyle. Starting earlier could lead to anxiety and weight gain, and make people generally more likely to make risky decision, reports the Guardian.

According to Kelley, these early days are making for an international community of sleep-deprived drones. "Staff are usually sleep-deprived. We've got a sleep-deprived society," he said, adding, "Sleep deprivation is a torture. Thirty days without sleep and you die. It has about the same effect as not eating."


Sleep deprivation has been linked to a number of physical maladies. One recent study found that those who sleep six hours a night or less are four times as likely to catch a cold than their longer-sleeping counterparts. Another found that timing is as important to sleep as quantity, so going to bed earlier might not make all that much of a difference to how tired we are. Yet another, also from Oxford, found that early risers process information as though they are drunk.

Kelley, his fellow sleep researchers, and other organizations in the UK are collaborating on a Teensleep project, which hopes to study teens at roughly 100 schools that would opt-in to later start times for the study. If this project extends to non-teens, we would happily take part.


Danielle Wiener-Bronner is a news reporter.