Getting a good night's sleep can make the world of difference to the day ahead, but getting enough shut-eye might be more important than many of us think.
Scientists from the universities of Oxford, Cambridge, Harvard, Manchester and Surrey examined the health implications that come with a lack of sleep for the BBC's Day of the Body Clock programme.
"We are the supremely arrogant species; we feel we can abandon four billion years of evolution and ignore the fact that we have evolved under a light-dark cycle," he said.
"What we do as a species, perhaps uniquely, is override the clock. Long-term acting against the clock can lead to serious health problems."
Professor Charles Czeisler of Harvard University also warned about the dangers of spending too much time using tablets, laptops and smartphones. These will increase our light exposure and lead to disruptions to the body clock.
"Light exposure, especially short wavelength blue-ish light in the evening, will reset our circadian rhythms to a later hour, postponing the release of the sleep-promoting hormone melatonin and making it more difficult for us to get up in the morning."
In the long term, the professor said this can cause "chronic diseases."
Just another reason why she should probably put down the iPad and concentrate on getting some shut-eye instead.
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