The digital age is forcing our body clocks to revert to an ancient sleeping pattern, writes Lori Anderson
Nigella Lawson, Britain’s national dish, has a secret. As sofa-bound voyeurs, we have all watched her pad into the kitchen at midnight in a state of tousled dishabille, her unctuous curves straining beneath the sweep of her casually-knotted black satin dressing gown, she reaches into the fridge for a few dollops of something sinful.
What we are not privy to, however, is what happens next: the domestic goddess returns to her boudoir, lets the puddle of satin fall to the floor, slips between the sheets and reaches for her piece de resistance – bright orange lab goggles.
As she said recently: “When I go to bed at night, I look like a sniper.”
Don’t worry, Nigella and her husband Charles Saatchi aren’t playing paintball, the reason for their nocturnal shenanigans, is that – like so many of us – the author and chef is finding a good night’s kip in short supply. The culprit behind the sleepless nights being her predilection for three in a bed: herself, Charles and the lure of that irresistible modern-day siren the iPad.
The blue-soaked light from such electronic devices as laptops and Kindles suppresses the production of melatonin, the hormone that maintains the body’s circadian rhythms and helps regulate sleep. Blue light is to the Sandman is as kryptonite to Superman: it leaves him curled up in a ball and so unable to sprinkle the sand into our eyes that hastens sleep.
The Sandman has been absent not just from Nigella’s bedroom, research shows that 60 per cent of us have some degree of difficulty with sleep, with 30 per cent of us suffering from insomnia.
Napoleon may have said that a man needs six hours sleep, a woman seven and a fool eight, but modern scientists are a little less harsh. While we are at our best on seven to eight hours sleep a night, we don’t necessarily need them consecutively.
The warm and languid eight-hour trip onboard the Slumberland Express is a relatively new development for mankind, who until the late 18th century enjoyed two bouts of sleep, each of roughly four hours but broken up by a period of an hour or two of wakefulness to be spent smoking, reading, praying or – for the French at least –making love.
French doctors in the 16th century recommended that couples wishing to conceive have sex “after the first sleep” as then they were liable to “do it better”.
The two bouts of sleep was noted by Homer in The Odyssey when he wrote: “In his first sleep, call up your hardiest cheer/ Vigour and violence, and hold him there/ In spite of all his strivings to be gone.”
The two sleeps began to be fused into one in the late 18th and early 19th century when lighting systems improved, allowing people to stay up later as well as diminishing the dangers of the dark. And by 1829, medical journals were advising parents to force children to accept one extended sleep instead of two.
Yet, those circadian rhythms are still buried deep within us. Anthropologists have found that bimodal sleep pattern, as it is known, is still found within all primitive societies which live without artificial light.
When Dr Thomas Wehr of the National Institute of Mental Health conducted an experiment in the 1990s, he discovered that volunteers faced with 14 hours a day spent in the dark would, after just one month, regress to sleeping in two blocks of four hours broken up by a period of restful activity.
Perhaps those of us who wake in the middle of the night should try to embrace it as a natural time of mystery and wonder, instead of one of anxiety and dread.
Ted Hughes certainly did. He would actually set an alarm to stir him in the middle of the night when he would rise to write poetry as he believed at these small hours he was closer to the heart of the natural world. However, this is of little comfort to the office worker panicking about not getting his or her recommended eight hours.
But Robert Ekrich, the author of At Day’s Close: Night In Times Past, a landmark study of sleep, said that because we believed we should be sleeping all through the night we become anxious when we awake, which perpetuates the sleeplessness. He argued that, instead, we should accept it. Oh, if only it were so simple. I’ve witnessed my share of long, dark nights followed by a “rosy-fingered” dawn and would agree with the research that pegs depression, low self-esteem and lack of positivity to sleep deprivation.
There is a weight and heaviness that comes from a lack of sleep that is truly miserable, but the toll is not just mental, but physical. Earlier this week, the Sleep Research Centre in Surrey reported that lack of sleep disrupted 700 genes that are crucial to maintaining our health as well as those linked to fighting off disease and stress.
While previous studies have shown that people who enjoy less than five hours sleep a night (roughly 5 per cent of the population) have a 15 per cent greater risk of death, scientists are now inching closer to an explanation as to why.
The new research possibly shows how a lack of sleep changes the genes that control metabolism and so may exacerbate diabetes or obesity, while changes in other genes that regulate our inflammatory responses may lead to an increase in heart disease.
The recipe for a good night’s sleep and a longer, healthier life is for us all to improve our “sleep hygiene”, which means banishing all electronic devices not only from the bedroom, but also an hour before bedtime which, as for toddlers, should be at the same time every night if we wish to keep our circadian rhythms regular.
Should we all give it a try? I think I’ll sleep on it.