25 Things You Need to Know About Sleep
Will a lack of shut-eye make you fat? Do white-noise machines cause deafness? Are night owls wealthier than early birds? Wake up to the secrets of slumber.
Had a Terrible Sleep? Get Someone to Lie to You
It’s the ultimate mind trick. A paper published last year in the Journal of Experimental Psychology showed that when students were told they got a good sleep, even if they didn’t, they performed better on tests than those who were advised their slumber was truly subpar.
Sleep Machines Won’t Damage Your Hearing- or Your Baby’s
A controversial study from Toronto’s Hospital for Sick Children released last year identified white-noise machines as a possible cause for hearing loss in infants. And while results showed potential for damage, researchers found that little ears were at risk only if a machine was turned up to maximum and placed in close proximity to the infant. Nothing dialing down the volume and leaving a wide berth can’t fix.
Why Any Sleep is Better Than No Sleep (No Matter How You Feel When You Wake Up)
While the idea of pulling an all-nighter to ensure you make that 4 a.m. flight or ace that early-morning presentation might be tempting, take a nap instead. A study of airplane pilots by NASA reveals that catching any shut-eye at all, even as short as 26 minutes, will boost your cognitive function when you wake.
The Best Naps are Either Short or Long
A “power nap” (10 to 20 minutes) can restore alertness without accompanying feelings of “sleep inertia,” a.k.a. post-nap grogginess.
A 90- to 120-minute nap also avoids sleep inertia and helps with mental processing, not just alertness. It is a full-cycle sleep, during which the brain moves through slow-wave deep sleep and into REM-stage sleep, associated with dreaming.
…But We Stay Asleep Longer
According to the survey of six countries, Japanese citizens get the least amount of sleep per workday, clocking in at six hours and 22 minutes. Americans are nine minutes ahead, while Canadians snooze for seven hours and three minutes.
Socks are Conducive to a Sound Slumber
Canadians are more likely to sleep with socks on than Americans, Germans, Japanese, Brits and Mexicans-one in five of us do it. It pays to keep our toes toasty: having warm hands and feet helps us fall asleep more quickly and allows the body-which drops in temperature most drastically during REM sleep-to stay regulated throughout the night.
Avoid Screens in the Evening (or Follow This List)
Science says you should stop looking at TVs, computers, cellphones and tablets for at least two hours before you go to sleep. But for most of us, that’s not realistic. Here are some tips for shutting down your brain at the end of the day-even when you can’t let go of that iPad.
– Turn down the heat. Most people’s bedrooms are kept too warm for the body to sleep well, says Dr. Atul Khullar, director of Edmonton’s MedSleep clinic. Keep your room as cool as possible without being uncomfortable-between 18.5 and 21 degrees Celsius-and don’t forget those socks.
– Get the tech out of the bedroom. The blue light-light that is richer in short, or “blue,” wavelengths-emitted by most screens suppresses the secretion of melatonin, which will shift your circadian rhythm and keep you awake. Try switching out screens for a paper book before bed.
– Buy an alarm clock. Although your smartphone’s alarm will do the trick, chances are you’ll scroll through email, read the news or check an app when you should be focused on dozing off. “Alarm clocks have been around for 150 years and cost $9. Use one,” says Khullar.
– Have a light snack. Avoid proteins or fatty foods one or two hours before bed (the burst of energy they provide will keep you up), and opt instead for a small serving of a complex carbohydrate like cereal.
Canada’s Sleep Guru Says We All Need More Shut-Eye
Dr. Charles Samuels is the medical director of Calgary’s Centre for Sleep and Human Performance. He works with elite athletes, including Canada’s Olympic team and the Calgary Flames, to design detailed sleep, recovery and travel plans to help them manage jet lag and high-intensity training. He then studies the plans’ effectiveness to learn how the rest of us can perform better.
What are some of the rules athletes under your care have to follow?
The No. 1 rule in sleep for athletes-or for anybody-is they need to get more. They need to get rid of all technology and use caffeine strategically-one or two cups of coffee in the morning and another just after lunch if they’re still able to fall asleep at night. The best way to mitigate fatigue is a cup of java right before or after a short nap.
What’s your own sleep schedule like?
It’s routine. I watch TV until 11 p.m., then go to bed and read for a few minutes. I get out of bed by 7 a.m., and I always close my eyes midday for 10 to 15 minutes of rest.
How can your sleep work with the Olympic team be applied to the average human?
Our health is affected substantially by being active. While that sounds pretty simple, it’s amazing how long it’s taken to get the evidence in scientific literature to show that activity affects appetite and our mood. Sleep has a direct impact on appetite. An underlying barrier to activity is fatigue, which is a function of not getting enough sleep. As you get less sleep, the appetite for high-calorie, dense foods goes up, so it ties back to a really important health issue in North America: more sleep will reduce obesity.
Sleep and Obesity Are Locked in a Vicious Cycle
22%: Extra calories consumed by men who slept for four hours versus eight hours in a 2010 study published in The American Journal of Clinical Nutrition. Neither the well-slept nor under-slept participants said they felt hungrier or enjoyed the foods more, yet the tired group consumed substantially more calories during subsequent meals.
Scientists Can See Your Dreams
Using an MRI machine and an algorithm, doctors in Japan can infer from brainwaves what their test subjects are dreaming about. “Dreaming has been thought to be a private experience, accessible only to the person experiencing the dream,” says Yukiyasu Kamitani, of Kyoto’s ATR Computational Neuroscience Laboratories. But his lab has taken a glimpse behind the veil by assembling a database of commonly dreamt images (cars, buildings, men, women, food and even furniture) and correlating them with three participants’ brain activities, testing them more than 200 times each. With this data, Kamitani was able to guess what was dreamt 60 per cent of the time. It seems there’s no escape from our work and personal stresses: most dreams were about the office or the family.
Your Brain on No Sleep is Schizophrenic
Last year, researchers at the University of Bonn in Germany discovered that people who hadn’t slept for 24 hours experienced schizophrenia-like symptoms, including pronounced attention deficits, hallucinations and a skewed sense of time and smell.
Insomnia Isn’t About Falling Asleep
Or it isn’t just about that. Indicators of insomnia also include waking up too early, not feeling rested in the morning, irritability, depression, headaches and gastrointestinal distress.
Sleep Learning is Possible
If the chords of “Sweet Caroline” continue to elude you despite rigorous practice, press play on your iPod and take a nap. Scientists at Illinois’s Northwestern University have discovered that listening to a melody in slow-wave sleep helps cement it in your memory and you’ll play the tune better. The same principles apply to foreign languages, according to research from two Swiss universities. Review your vocabulary before you sleep, play audio of the words for 90 minutes whilegetting shut-eye, and you can anticipate better recall upon waking. ¡Excelente!
It Pays to Stay Up Late-Literally
In 2013, University of Madrid psychologists published a study that supported research concluding that late risers are more intelligent than early risers. But in the battle between those who burn the midnight oil and people who wake with the sun, who comes out on top?
Is Your Tongue Larger Than Average? You Might Be a Poor Sleeper
Obese men with obstructive sleep apnea were likelier to have larger tongues than those who slept normally, according to 2014 research. They also had more fat at the base of their tongues, leading researchers to hypothesize the appendage was blocking sufferers’ airways.
Nix the Nightcap: Alcohol Doesn’t Help You Sleep
Booze may ease the slide into slumber, but researchers have found it promotes wakefulness later in the night, not to mention restless leg syndrome, night sweats and trips to the bathroom.
Want to Promote Sleep? Don’t Count Sheep
Rather than audit a fictional herd of woolly mammals (something active), try picturing a restful scene (something passive). If you haven’t fallen asleep within 15 to 20 minutes, move to another room, take up a quiet activity, like reading, then try again.
We All Need a Primer on Sleeping Pills (Especially Teens and Seniors)
When to consider prescription sleep aids: Insomnia has been linked to serious health concerns like depression and risk of death from cardiovascular disease. Health agencies recommend sleeping pills to ease short-term sleep deficits or for very severe symptoms, but only after ruling out underlying health problems-and only if behavioural and lifestyle changes fail to get results.
Getting more exercise, quitting coffee by mid-afternoon, avoiding late meals and setting up a regular sleep routine can all help alleviate sleeplessness.
Who should be most wary of them: A third of older Canadians use sleeping pills, despite the risks for this age group, according to the health watchdog group Choosing Wisely Canada. Sleep aids can increase the risk of falls and lead to constipation and trouble urinating-while only marginally increasing sleep quality and length.
Trouble can occur at the opposite end of the age spectrum, too: Teens prescribed sleeping pills or anxiety medication were 12 times more likely
to abuse those drugs within the next two years, according to a 2014 study from the University of Michigan.
Men and Women Aren’t Created Equal
– Twice as many men suffer from sleep apnea, which interferes with nighttime breathing, compared to women. Snoring can be a symptom, and obesity a risk factor.
– Insomnia disproportionately affects women; complex hormonal cycles play a role. Doctors may prescribe sleeping pills as a short-term solution, but lifestyle changes, like getting more exercise (especially in the morning rather than at night), can make a big difference.
– Men tend to have worse-quality sleep than women but are less likely to complain about it. Good sleep is associated with good health, so it’s worth making a fuss to improve yours.
– Shouting, thrashing and grunting during deep sleep-which can result in injury-may be a sign of rapid eye movement sleep behaviour disorders, more commonly experienced by men aged 50 and up.
– A 2008 study conducted at North Carolina’s Duke University Medical Center found women who had sleep of lower quality were more likely than men with similar problems to have blood indicators associated with heart disease.
– Restless leg syndrome affects twice as many women as men. Pregnancy can be a trigger, but so can aging. Sleep deficits and alcohol worsen symptoms, so experts recommend sufferers eliminate both.
Driving While Sleepy Can Be as Dangerous as Driving While Drunk
17 to 19 hours: How long subjects in a 2000 study were deprived of sleep before they did as badly or worse on some performance tests as those with a blood-alcohol content of 0.05%-the level at which police will suspend your licence for drunk driving in most Canadian provinces.
Couples Who Sleep (Really, Really Closely) Together Stay Together
A British psychologist who recently asked 1,000 people at the Edinburgh International Science Festival to describe their preferred sleep positions and the quality of their relationships found this correlation: the further apart couples slept, the lower they rated their relationships.
94% of couples who spent the night in contact were happy with their relationships vs. 86% of couples who spent the night less than 2.5 centimetres apart and 66% who slept more than 75 centimetres apart.
Spooning: Uncomfortable but Popular
31% of couples from the same study slept facing the same direction. Spooning was beaten out only by the roomier back to back (42% of couples). Face to face was the position of choice for 4% of partners.
Caffeine Keeps You Awake by Being a Talented Mimic
Drowsiness occurs when a molecule in your body called adenosine binds to receptors in the brain, slowing down neural activity. Caffeine molecules look just like adenosine and can therefore bind to those same receptors, blocking off adenosine-and sleep. Instead, you get sped-up brain activity and a flood of adrenalin.