Busting myths and setting the record straight on what happens when we close our eyes.
In case you missed it, sleep is all the rage in 2017. Celebrities, ever eager to share questionable health advice, are leading the charge, with actress Gwyneth Paltrow declaring sleep’s healthful virtues and Huffington Post co-founder Arianna Huffington writing books and delivering TED Talks on the “sleep revolution”.
Now there are wearable gadgets and apps that monitor our activity patterns and help keep us accountable and aware of our habits.
And don’t forget the wellness centres with their flotation, levitation, zero gravity, anti-gravity, sensory deprivation rooms to help you be a better you.
Myth: Eating cheese before bed gives you nightmares (it doesn’t)
Even sleep is not immune to society’s whims and hunger for better, faster, more.
Whether these things are of any real benefit is up for debate (what’s not in doubt is how these fads help relieve you of your hard-earned cash).
Now, hear from a real sleep expert
“I think it is important that we talk about it even if it does get trivialised in some blogs and books,” says Dr Sarah Loughran, a Research Fellow from the University of Wollongong’s Faculty of Social Sciences.
Depending on the audience, she’s a cognitive neuroscientist or a psycho-physiologist. Her background is in neurophysiology and neuroscience, and she’s spent the past decade or so studying what’s happening in our brains during sleep as well as the effects of electromagnetics on our bodies, for example putting some real science into the question of what impact screen time has on children’s sleep.
Fact: The colour of bedroom lighting can affect your sleep. Blue is the strongest suppressor of melatonin, a key hormone that regulates sleep.
“Just being a topic on people’s minds is a good thing. Yet, we still don’t really know what the function of sleep is and sleep research, oddly enough, is a pretty new field of research,” Dr Loughran says.
Earning the title of “sleep expert” wasn’t really part of the plan when Dr Loughran started her PhD more than a decade ago.
“I really wanted to do something that I felt would make a difference, would be relevant to everybody. I could see how prevalent mobile phone use was and how little we know about sleep, and I could see this might be an area that could impact millions of people.”
Forget leg day, don’t skip sleep
Until relatively recent times, sleep was thought to be a conditioned response to tiredness. Other than a fascination with dreams, for those who can remember their dreams, sleep was something we did to recharge the batteries after a day of activity.
“We now know sleep is important for memory consolidation and for brain plasticity, and it’s incredibly important in development, when a child’s brain is continually growing and new connections are being reinforced,” Dr Loughran says.
Sleep deprivation is the equivalent of having a blood alcohol of .05, and it’s commonly used as a form of torture or training based on the same basic premise: lack of sleep induces high levels of stress and impairs our judgement and motor skills.
Myth: Never wake a sleep walker. (There’s no documented proof that waking a sleep walker can be harmful.)
“People know that it’s important to exercise and that it’s important to eat healthy, but I don’t think people really understand that it’s just as important, if not more important, to get adequate sleep.
“If you’re not getting adequate sleep, then you’re ruining all the good work you’ve done with exercise and eating.
“We’re living in a 24-hour society where people are trying to condense time to be able to do everything that they want to. And the first thing pushed aside in many people’s lives is sleep.”
Peak hour in dreamland
Part of the reason skipping sleep, or trying to get by on less, is not a good idea, is because the brain doesn’t take a break. Quite the opposite, it kicks into overdrive and gets busy filing and filtering all the information we’ve absorbed during waking hours.
“There are periods of sleep where the brain is even more active than when we’re awake,” Dr Loughran says. “It’s continually doing things like memory consolidation and working on brain plasticity.
“Brain or synaptic plasticity sounds really complicated, but the idea is that, for example, today from the morning till tonight, everything that happens to you, everything that you see, that you hear, that you do, is dumped in your memory.
“That’s massive volumes of information. Synaptic plasticity is a bit like a garbage disposal that filters out the unimportant information and then it starts to consolidate the information that you might need to remember. Today I might have had a great coffee. I’ll remember that, but my brain will throw out what colour the napkin was.”
Fact: Tiredness in humans peaks at 2am and 2pm every day
Given the business going on inside our heads while we sleep, the idea that we can’t bank sleep or repay a sleep deficit starts to make sense.
Despite the high-profile executives and entrepreneurs who claim to be able to function on three hours a night, a trait worn by some as a badge of honour and dubbed “the sleepless elite” by the Wall Street Journal, Dr Loughran says most of us fit in the seven-to-nine hours range.
For most people, living outside that window means getting too much or too little sleep, with the potential for long-term negative health impacts.
“You might think you feel OK, but in time this cumulative sleep deprivation is increasing your risk for health problems such as obesity or diabetes, and you don’t realise this is happening.”
Asleep in the lab
To see exactly what is happening inside our brains when we sleep, and how it can potentially be disturbed by things like lights and tablets or smartphones, researchers ask volunteers to nap in the name of science.
In the sleep lab, volunteers wear a number of sensors to measure brain activity that are used to distinguish the different stages of sleep.
“You have different stages and different cycles through the night, and we record those with the brain activity as well as some eye movement and some muscle movement,” Dr Loughran says.
There’s some irony in the fact that this research requires the scientist to skip sleep themselves to monitor the participant overnight.
Myth: Warm milk helps you sleep at night. (Not unless you consume carbohydrate-rich foods, which produce insulin and interact with the “drowsiness factor”, an amino acid called tryptophan.)
“Your brain activity during sleep is like a fingerprint. There’s a general structure of normal adult human sleep, but the actual content and the frequencies and patterns that I see from you are very specific to you, and that makes it a really good tool to look at several nights and measure the effect of something such as lighting or screen time.”
From the studies so far, Dr Loughran has seen that screen time could impact sleep in a number of ways: from increasing the amount of sedentary behaviour during the day, which has a flow-on effect on sleep, to over-stimulating our brains when we need to wind down.
The latest area of interest is the colour of light. iPhones come with a “night shift” light setting that turns the screen to a yellowish hue, based on the idea of using a colour of light that doesn’t suppress the release of melatonin from the pineal gland, located deep in the brain.
Fact: Before colour TV, about 75 per cent of people dreamed in black-and-white. Now it’s around 12 per cent.
“Suppression of melatonin can delay your sleep onset and change your sleep across the night,” Dr Loughran says. “One study has suggested that shining a bright light on the back of the knees resets the body’s internal clock.
“It suggested that shining light on the backs of knees prior to dawn advanced the circadian clock, so that by the next day the timing of temperature changes and melatonin release occurred earlier. But this hasn’t been replicated.”
If you’re having trouble sleeping, not reading your iPad or Kindle in bed might be a good idea. In fact, the American Academy of Sleep Medicine’s guidelines say the bedroom should be kept for sleep and sex only.
You can’t beat sleep
Just as what we do before we go to bed affects our circadian rhythm, trying to artificially alter sleep cycles with caffeine or other stimulants can do more harm than good.
“The reason you’re reliant on caffeine or energy drinks is because of your sleep deficit,” Dr Loughran says. “If you’re relying on something like caffeine, then there’s the addictive aspect of it as well.”
Sleep deficient. Two words that ring true for new mothers. Dr Loughran says the idea that mothers have a pregnancy-induced hormone that allows them to power on for months with little sleep is completely bogus.
“Just because they’re still functioning doesn’t mean lack of sleep is not having any impact physiologically and mentally. This is another area that lacks research and we need to look at the connection between sleeping and postnatal depression.”
Fact: In Japan, sleeping during work is viewed as a positive sign of exhaustion from working hard. While in North Dakota, it’s illegal to lie down and fall asleep with your shoes on.
Beyond the science, Dr Loughran says what women are told about how they should cope with life after the birth of a child is creating unrealistic and potentially dangerous expectations.
“A lot of women feel like they can’t say, ‘I just feel like shit right now’, because you’re not supposed to. You’ve got a newborn baby, you’re supposed to be over the moon and happy and everything’s supposed to be perfect.
“Yet, they’re getting one hour of sleep a night, they feel terrible, then they’re worried if their baby isn’t sleeping but there’s these images and messages about some celebrity’s ‘baby body’ and they feel they can’t talk about these difficulties.
“Even before the birth women tell me, ‘I’m this big and I can’t sleep. It’s heavy and I’m uncomfortable and I can’t sleep in any position other than on my back’. They’re already starting off with poor sleep and there’s not much practical information given to new mothers about all this.”
Fact: Giraffes need about 5 minutes to 2 hours of sleep per 24-hour period, while koalas can sleep for 20 hours per day
For all the apps that are supposed to wake you at an optimal time, for all the faddishness about sleep and how we can do it better, our bodies know best. They have inbuilt rhythms and patterns, if we let them do their thing.
“If we had a healthy sleep–wake schedule we really wouldn’t need alarm clocks,” Dr Loughran says. “If you’re getting enough sleep your body would just naturally wake up and you would feel better. But that’s in an ideal world and we don’t live in an ideal world.”
So, close the laptop, put down the phone, turn off the TV and go to bed. It’s good for you.