A good sleep makes everyone sharper, healthier and calmer – especially teens
Sleep is for losers. Kush Thaker, 17, doesn’t say so explicitly – he’s a student politician, after at all – but it’s clear that he has been sold on the awake-is-great ethos of modern society. Pulling an all-nighter is “glorified.” The notion that he may spend one-third of his life sleeping is “daunting.” He admires the entrepreneurs whose “brilliant ideas strike at 4 a.m.” High achievers, he explains, “are expected to forgo sleep.”
And Kush has better things to do, including Grade 12 homework, texting, updating his Facebook page, working on a national youth blog and his obligations as a Toronto school board student trustee. He estimates that he gets four to six hours a night. “I know it’s not good, but I have gotten used to functioning while drowsy,” he says. “I wish I did get more sleep. But it’s just rationally weighing the costs and benefits. Sleep is my reserve time.”
But a growing body of brain science and behavioural research serves as a wake-up call to the fact that his calculation is wrong.
For one thing, sleep is an investment that reduces stress and improves productivity. Last year, Harvard researchers estimated that chronic sleep deprivation was costing U.S. companies $63.2-billion annually, because dozy employees are less effective.
Research shows that good sleepers are less likely to smoke, more likely to exercise, and drink less alcohol. Athletes who sleep longer perform better.
Getting extra sleep, a recent study found, really does produce better test results than using the time to crack the books. Sleep even keeps us svelte – when tired, we’re much more likely to be seduced by salty French fries.
It is no coincidence that, over the past 50 years, citizens of the industrialized world have, as well as getting fatter and more anxious, lost about an hour of sleep a night – roughly one full night’s worth every week. And because of city lights, social media and such habits as eating and exercising later at night, what sleep remains is often not the soundest. As Till Roenneberg, the author of Internal Time, points out, 80 per cent of the world now needs an alarm clock to get up each morning. As a result, the head of human chronobiology at the University of Munich’s Institute of Medical Psychology says, we live in a permanent state of “social jet lag.”
And no segment of the population is more jet-lagged than teenagers. Surveys show that no fewer than three-quarters of them fail to get the rest they need, and find themselves in school the next morning expected to learn when their brains want them to sleep.
Society is increasingly torn when it comes to sleep – we lament its loss even as we boast of how little we require. Because rising at dawn made more sense when most people were farmers and candle wax was expensive, the shift from early bird to nighthawk seems of no great consequence.
Yet as science demonstrates how, without enough sleep, the brain falters, there is a growing campaign to turn back the clock. Researchers are calling for more specific school-based interventions, particularly for elementary students, to establish better sleep habits early on life, and to make sleep education more central in health classes.
And what exactly will happen if nothing is done to help people get a decent night’s sleep – can we adapt and learn to thrive with less rest? Scientists admit that they don’t know, but the early indications suggest that society’s new bedtime story won’t have a happy ending.
“We have all heard of healthy eating – the same thing has to happen now with sleep,” says Reut Gruber, a clinical psychologist at McGill University who studies sleep and has created an education program for elementary students in Montreal-area schools.
Adults’ bad habits, she says, are setting an unhealthy pattern because kids get the message that sleep is “a waste of time.” But good diet and exercise won’t make us healthy, if we don’t sleep well at the end of every day.
Dr. Gruber is leading a national committee of psychologists, pediatricians and scientists that is developing new guidelines for healthy sleep for children and youth and strategies to prevent sleep deprivation. When it comes to public health policy, prominent researchers argue that sleep deserves a higher profile – right up with making sure a child gets 60 minutes of exercise a day.
In fact, stressing exercise without giving sleep equal weight may have done some harm, suggests Mark Tremblay, director of the Healthy Active Living and Obesity Research Group at the Children’s Hospital of Eastern Ontario in Ottawa.
Dr. Tremblay led the committee that revised the Canadian Physical Activity Guidelines last year, and says that “sleep has been largely lost in this discussion” even though it is vital to a healthy lifestyle.
He worries that parents feel that it’s enough to take their kids to hockey practice on Saturday morning. “As a parent of four kids, I don’t know if I can recall … when I have ever talked casually to neighbours about sleep as an important thing in our children’s lives …,” he says.
“We need to draw sleep into the popular vernacular.”
In Grade 9, to stay awake in class, Ottawa student Andrew Zeigler chugged Monster energy drinks regularly. “I knew it would give me a jump start,” he says, “almost like a car that’s broken down.” Then he began to worry about what was in what he was drinking, and switched to slushies for his midday jolt.
Now, in Grade 11, he’s trying to eat a good breakfast, but with just five hours of sleep most nights, he still feels that he is running on empty. Even so, he has trouble falling asleep: “My mind is on a lot of things.”
Teenagers may be dozy by nature, and concern about children not getting enough sleep goes back more than a century, but research shows that young people really are sleeping less than their parents did at the same age. If anything, culture has shifted away from helping teenagers sleep, with the distractions of 2 a.m. texts, and pressure of extracurricular activities and school performance.
It’s a common teenage tale: In a survey released this week by the Toronto District School Board, 29 per cent of high-school students said they “lose sleep because of worries” and 48 per cent said they feel “tired for no reason,” often if not all the time.
None of the 10 high-school students who commented for this article gets more than seven hours a night, and half admitted to having nodded off in a morning class. They all want more sleep, but none quite knows how to get it.
An obvious solution is to delay the start of the school day. One U.S. study found that pushing school starts times by just one hour improved academic performance and attendance. Many high schools still start at 8 a.m. or shortly afterward – which Dr. Roenneberg, the German sleep researcher, considers evidence of “the enormous discrimination against these young children who are brought to school in the middle of their internal sleep.”
He cites studies that show the academic disadvantages vanish in university, when students can choose later classes.
How much sleep people need and whether they would rather rise early or late are decided by genes, age and how much light they get. There is even a physiological explanation for why teens are notorious for sleeping late. During puberty, melatonin, the hormone that regulates the sleep cycle, is released in the body later in the evening – around 9 or 10 p.m. This makes it difficult for teenagers to nod off early, and nearly impossible, given family and school schedules, for them to get the optimal nine to 10 hours that health guidelines suggest they need.
What’s more, Dr. Roenneberg suggests, our body clocks are out of sync with modern life. “They evolved thinking we would be outside in broad daylight during the day and inside in pitch darkness during the night. We are not living that way any more.” As a result, we get by on less sleep than we need, and spend every night trying to catch up.
Brain experiments and behavioural studies show that this is an unhealthy habit, for memory, cognition and mood at every age. Sleep, in such short supply for today’s adolescents, may be especially important for development during puberty.
And the quality of sleep is a key factor: A Harvard University study released in September found the hormone that triggers ovulation in girls and testosterone production in boys was most actively released by the brain during deep sleep. In a recent experiment at Brock University in St. Catharines, Ont., sleep-deprived students were found to have suppressed levels of testosterone, and, compared with a control group, were less motivated to challenge a cheater in a card game.
“You are effectively blunted to do anything inspirational or active, you don’t really care about anything,” says psychology professor Kimberly Cote, who led the study. In another experiment, Brock researchers found that sleepy subjects took significantly longer to notice errors in a computer test than a well-rested control group.
Neuroimaging experiments are also unravelling the stages of sleep – to unlock the role it plays in consolidating memory and controlling behaviour.
At the University of Montreal, researcher Stuart Fogel is conducting studies in which subjects sleep in a magnetic-resonance imaging (MRI) machine after learning a new memory task to see what parts of the brain are active as they rest. (In another experiment, he found that young adults who napped after learning a task performed it better after waking than those who stayed awake.)
Research elsewhere is exploring how sleep is different for people with mental disorders such as schizophrenia. Several papers published last year used MRI scans to show that, when people were short on sleep, the higher-thinking region of the brain that dictates food choices was impaired, leading them to crave sweeter and saltier tastes. Research is also revealing the potential long-term implications of poor sleep – another recent study found a link between sleep and insulin resistance in teenagers, which could affect the risk of diabetes later in life.
And yet a little more sleep goes a long way. In one of Reut Gruber’s recent studies, giving just 27 minutes more sleep to children who are 7 to 11 shows improvements in their emotional behaviour in school, and a significant drop in reported sleepiness. (Dr. Gruber reports similar findings with children with attention-deficit disorders.)
As for Kush Thaker, he has accepted his sleepy adolescence – dozing off in morning classes, catnapping (along with many of his peers) during study period and resorting to the occasional Red Bull, although lately, he is more likely to try water – “drinking, splashing, whatever works.”
Mathew Pilon, 17, a Grade 12 student in Port Colborne, Ont., quips that, unless “the Earth’s rotation slows drastically somehow, … I’m stuck with drowsy morning and sleepless nights.”
The problem is that those drowsy mornings and sleepless nights add up to a lifetime of sleep deficits.
And even if science is still struggling to assess whether the end result will be good or bad, “the impact of poor sleep on society is rather under-appreciated,” a tactful Stuart Fogel says.
by Erin Anderssen
Source: The Globe and Mail