If you’re not sleeping well lately, you’re not alone. Insomnia, broken sleep and weird dreams have all surged during recent months, according to both scientists and a spike in google searches.
I’ve been interested in sleep for a few years now because up until COVID I was hopscotching timezones every few weeks due to work travel, and it took its toll on my body clock. Then, like so many, my sleep quality took a hit after lockdown, so, as a completely non-medical, non-scientific layman, I began circling back to what I’d already learnt and exploring even more of the science and advice around how to nurture sleep.
If you’ve struggled with sleep in recent days, here’s why you should treat it as more than a little annoyance, and what you can do about.
The Sleep Problem
Even before COVID, the World Health Organisation had identified the drastically reduced amount of sleep across the industrialised world as a global health epidemic. Evidence shows that we are now getting 1.5 to 2 hours less sleep per night than we did in the 1950s. Yet our bodies haven’t changed. Sleep researcher Matthew Walker writes that “there does not seem to be one major organ within the body, or process within the brain, that isn’t optimally enhanced by sleep (and detrimentally impaired when we don’t get enough”.
The question of what constitutes ‘enough’ is, of course, the key issue. Researchers consistently show that almost all adults require somewhere between seven to nine hours of sleep per night. As Tom Rath puts it, “Most people need seven hours of sleep just to be in the game the next day and ideally eight to have enough energy to win.” Yet even before the pandemic struck a blow to many people’s sleep, 65% of Americans and 66% of Japanese were not reaching that threshold, and a third of Britons and Americans were getting by on less than six.
The bottom line is that half of all adults across all developed countries will not get the necessary amount of sleep they need over the coming week.
We tend to think of that, though, as simply a fact of modern life. So does it really matter?
Without sleep, you’re dumb, dangerous and stressed (just to start with)
Research has found that sleep-deprived individuals take 14% longer to complete a task and make 20% more errors. And if you’re trying to learn anything, the sleep you get the first night after learning is critical. Get less than you need, and your memories simply can’t properly consolidate that learning. Our performance in the workplace also suffers from lack of sleep. Individuals who sleep less than seven hours a night cost the economy around 2% of GDP – or, a cost of upwards of $2000 per person to their company per year. As one researcher from Harvard Medical School puts it –
“Americans are not missing work because of insomnia. They are still going to their jobs but they’re accomplishing less because they’re tired. In an information-based economy, it’s difficult to find a condition that has a greater effect on productivity.”
A significant percentage of people are operating on less than the required amount of sleep, yet still undertaking activities like getting behind the wheel. Perhaps it shouldn’t be surprising then, that Walker tells us that “vehicle accidents caused by drowsy driving exceed those caused by alcohol and drugs combined.” Indeed, after 10 days of just six hours of sleep, one study found that the brain is as dysfunctional as it would be after going without sleep for 24 hours – yet sleep-deprived brains can’t accurately sense how sleep-deprived they are. On less than five hours of sleep, you are three times as likely to get into a crash. On four hours or less, it’s 11.5 times. One study showed that four hours of sleep loss – say, getting four hours instead of eight – produces the same impairment impact as a six-pack of beer. Yet many people are on the roads in exactly that condition.
When we don’t get enough sleep, it ramps up our sympathetic nervous system, putting us in some degree of the fight-or-flight state. It increases the level of the stress hormone cortisol, constricting blood vessels and increasing blood pressure and heart activity, which can increase the likelihood of heart attack, heart failure and stroke. It is during our deep sleep, or NREM sleep, that the brain calms down this reaction, so chronic under sleeping can mean sustained stress signals flooding through our body.
It’s hard to overstate how many health implications a lack of sleep has. It has been proven to increase our vulnerability to cancer, Alzheimer’s, heart disease, stroke, infection, diabetes, mental health issues and more. One 14-year study found that men with poor sleep quality were twice as likely to have a heart attack and four times more likely to have a stroke, even after controlling for other factors. Another showed that regularly getting less than six or seven hours a night doubles your risk of cancer and that just one night of only four hours of sleep can sweep away 70% of our natural cancer-fighting cells. Studies have also demonstrated that healthy individuals limited to four hours of sleep a night for six nights were found to have blood sugar readings that would classify them as pre-diabetic.
Another study tested how effectively participants’ bodies ‘correctly’ responded to a flu vaccine by generating antibodies. Those on seven to nine hours a night in the week before the shot had a powerful antibody reaction expected of a healthy immune system. Those whose sleep had been restricted produced less than half the immune reaction. The same results have been shown for other vaccines. Further, even three weeks of full sleep afterwards still never led to a full immune reaction if they were underslept at the time of the initial shot.
Walker states it bluntly – “When your sleep becomes short, you will gain weight.” The reasons for this are multiple. When you don’t get the required amount of sleep, you are hungrier, you crave more unhealthy food, your ‘full’ signal is suppressed and you don’t absorb nutrients as well. Further, and even more discouragingly, if you are working to lose weight through diet and exercise, your body will burn muscle rather than fat when you are sleep deprived. And this doesn’t just apply to adults – three-year-olds who get 10.5 hours of sleep or less are 45% more likely to be obese by age seven compared to those getting 12 hours, a health condition that can then lead to increased risks of many others.
The REM part of our sleep is when we dream, and this state fuels creativity. It takes the new information we’ve encountered during that day and begins making connections – especially distant, non-obvious connections – with other pieces of information already stored in our memory. It makes it more likely we can go into the next day able to find new solutions to existing problems, or come up with new and innovative ideas.
Conversely, it’s been found that when presented with different work tasks, people who have obtained less sleep will consistently select less challenging tasks, and come up with fewer creative solutions in the process. In other words, if you’re not getting enough sleep, you’re going to approach your work with boring, obvious approaches to problems and tasks – you’re not going to be the one to lead your team or organisation in new exciting directions or come up with that breakthrough product idea.
A study of healthy young adults had one group sleep normally while the other stayed awake all night. The following day, they scanned their brains while showing them the same set of 100 pictures with different emotional associations, from neutral (like a basket) to negative (a burning house). Those who were sleep-deprived had a 60% amplification in the emotional reactivity part of the brain compared to those who were well-rested. Similarly, another test showed that without enough sleep, participants couldn’t accurately ‘read’ the emotional cues of facial expressions, reading a lot more negativity and menace into neutral or friendly expressions.
Alongside our interpretation of events outside ourselves, those who are under-slept have been found to be a lot more volatile and rash in their own choices and behaviours. Workplace studies have found that lack of sleep makes it much more likely that an employee will lie or engage in unethical behaviour.
What to do about it
If so much is at stake, then, when it comes to our sleep, what steps can we take if we, like many others, have been struggling with it?
The amount and type of light that we’re exposed to both during the day and at night can impact on the quality of our sleep. Sunlight exposure during the day, and especially in the morning, helps regulate your internal clock and your melatonin levels. Indeed, one study of office workers found that those who didn’t have direct access to windows at work got 173% less exposure to natural light and as a result step an average of 46 minutes less each night. During the evening, light can have a damaging effect on our sleep regulation. Exposure to room light during usual hours of sleep suppresses melatonin levels by more than 50%, and blue LED light at night is particularly harmful, meaning that having dimmer, warmer lights in your home in the evening can help you transition to sleep more effectively. Avoiding light pollution in the bedroom itself during sleeping hours is also important.
- Try to get 30 minutes of sunlight during the morning – the earlier after waking the better.
- Make your bedroom as dark as possible during sleep. The ideal environment is dark enough not to be able to see your hand in front of your face.
- Try to avoid bluer LED lights in your home in the evening, and go for warmer, dimmer lighting.
You probably don’t need to be told that using devices in the evening can negatively impact on your sleep. A recent study of iPad use before bedtime found that it suppressed melatonin release by over 50%, delaying its normal ’sleep time’ rise by up to three hours. Users took longer to fall asleep, lost significant amounts of REM sleep, felt less rested and sleepier the next day, and, perhaps most troubling, experienced a 90 minute lag in their evening rising melatonin levels for several days after stopping nighttime use of the iPad.
- Set a timer for at least 60 minutes before your bedtime to stop using devices
When it comes to caffeine and sleep, one of the things we have to come to terms with is the fact that science says something different from what our own perceptions say. Research participants who still had significant caffeine in their system when it came time to sleep didn’t register a subjective difference in the quality of their sleep when asked the next day, but the results of their monitored sleep told a different story. In reality, they were getting measurably less REM and deep sleep.
Caffeine can also mask our body’s natural sleep-provoking impulses. There’s a chemical that builds up in your brain each day, starting from the time you wake up. It is called adenosine, and as it builds it latches onto receptors and creates something called ’sleep pressure’. Unfortunately, caffeine works to make us feel alert by latching onto the exact same receptors, blocking the path for adenosine and masking our natural sleep pressure until it clears. Further, caffeine actually causes your body to product two hormones that are anti-sleep – adrenaline and cortisol.
Unfortunately, the half-life of caffeine is five to six hours, which means that 12 hours after your last cup of coffee, a quarter of it is still in your system. So if you have your last cup at 2, then at 8pm only half of it has cleared.
- Start experimenting with stopping your caffeine intake at earlier points in the day than you currently do.
Some studies have found that magnesium can contribute to deeper, uninterrupted sleep. Food that are high in magnesium include green leafy vegetables, nuts like almonds, Brazil nuts and cashews, oatmeal, avocado and brown rice. You can also buy topical magnesium that you can apply directly to the skin, and that can help ease sore muscles.
- Consider whether increased magnesium-rich foods could assist you in getting your recommended daily intake.
It’s bad news for those who enjoy a nightcap, but according to sleep researcher Matthew Walker, “alcohol is one of the most powerful suppressors of REM sleep that we know of.” This is particularly true for women, who although it can help them fall asleep faster, are even more likely to have their sleep disturbed by waking up more often and get less overall sleep than men with equal breath alcohol levels.
- Consider reducing the frequency of your alcohol consumption
- Wrap up any alcohol intake at least three hours before bedtime
Meditation and Relaxation
Deliberate relaxation and meditation activities can improve the quality of your sleep. The American Academy of Sleep Medicine published research showing that over a two month period, a raft of measurements of sleep quality were positively impacted by meditation practised during the day. Similarly, relaxation exercises in which you lie down and consciously move through a process of tensing and relaxing muscles down from your head to your toes has helped some to relax and transition into sleep more easily.
- Experiment with meditation and relaxation practices.
Both exercise as we typically refer to it, and general increased movement throughout the day, can help improve sleep. One study found that 150 minutes per week (for example, 30 minutes five times a week) of moderate to vigorous exercise improved sleep quality by 65%.
- Whatever your current level of movement or exercise, consider how you could start experimenting with increases, like a standing desk if you normally sit all day and don’t exercise, or an increase in intensity if you already do low-intensity exercise each day.
A hot bath isn’t just relaxing – it has been scientifically demonstrated to positively impact on sleep. The heat invites blood to the skin’s surface, which in turn means that when you get out, those dilated blood vessels mean you quickly lose heat, and your core body temperature reduces. As a result, you can fall asleep more quickly because your core is colder, and you can also potentially experience 10-15% more deep NREM sleep.
- Try having a hot bath around 90 minutes before it’s time to sleep.
Speaking of temperature, keeping your bedroom chilly can help you sleep. Some indications are that a temperature between 15 and 20 degrees Celsius, or 60 to 67 degrees Fahrenheit, can nurture sleep by helping you fall asleep, ensuring melatonin regulation, promoting more effective glucose disposal, and improving the quality of our sleep.
- If you have the ability to regulate the temperate in your bedroom, choose a cool temperature once it’s time to sleep. If you don’t, experiment with other ways to keep the room cool like powerful fans.
What you eat at night can also impact on your sleep. Diets that are high carb and low fat, or high sugar, have been found to decrease the amount of deep NREM sleep and increase the frequency of awakenings during the night. However, there are also nuances. Easily digested carbs four hours before bedtime can help you fall asleep fast, but any closer to bedtime they can interfere with sleep. You should generally avoid eating within 90 minutes of heading to bed, but if you really need a bedtime snack, the best option right before bed is a high-fat, low-carb snack, to ensure you don’t experience a blood sugar spike during sleep, which can interfere with your sleep quality.
- Experiment with how changes to your levels of carbs, sugar, fat and protein in your diet can impact on your sleep.
- Avoid eating within 90 minutes of bed, but if you need something, try to ensure it’s low carb and low sugar.
Constant, steady background noise (as from a steady fan or a white noise machine) has been found to be effective in improving sleep quality. Part of the reason for this is that it can mask the irregular noises that can commonly occur in the vicinity of our modern living arrangements. Whether it’s other people moving around in the house, a neighbourhood pet or neighbours closing car doors outside your window, these kinds of noises can either wake us fully from sleep or simply disturb our ability to stay in deep sleep. Steady background noise can help create an audio ‘buffer’ that can reduce the impact of irregular sounds.
- Explore white noise options like in-ear buds, white noise apps or machines, or a fan that provides a steady level of background noise that doesn’t interfere with your sleep.
Pretty much everything I’ve ever read about sleep says the same thing – consistency of sleep schedule, especially keeping the same wake time every day, is one of the best things you can do for your sleep quality. This has always frustrated me, because I was always travelling and changing timezones, but also because I work with a team that lives across timezones, and therefore my ‘office hours’ vary greatly. However, the evidence was so compelling that, even though I can’t do it perfectly, I have been trying more than ever during the enforced-travel-ban of COVID to establish a somewhat consistent sleep schedule.
- Try to map out a rough ‘ideal plan’ of your sleep and wake times that you can work to try aligning with as much as possible, possibly iterating over time.
This one is a personal recommendation only, but if you’re anything like me, tracking your sleep can also help you to improve it. I have an old Apple Watch that I only use at night, set to do not disturb and cinema mode, so it doesn’t get any notifications or light up when I move around. It connects to the AutoSleep app on my phone (which I charge overnight down the hall in another room). It tracks how much sleep I get, including my percentage of deep sleep, and the number of times I wake up or move into a very light sleep during the night. Seeing the data right there helps me get an accurate idea of how my sleep is improving, or where I need to make sure I am really prioritising it better. There are of course a range of wearables and apps you can use for this purpose.
- Consider whether some mechanism of sleep tracking might help you improve your understanding of your current sleep health, and monitor which steps are working to help you sleep better.
As much as I hate to say it, as someone who has experienced the extreme exhaustion of being unable to sleep three days into a 13-hour timezone difference, sleeping pills – even mild and over-the-counter versions – are increasingly proving in scientific studies to be much more dangerous than was previously realised. Even occasional use – defined as 18 pills in a 12 month period – has been shown to increase mortality rates by 360%.
Another study showed that individuals taking sleeping pills were 30 to 40 percent more likely to develop cancer within the two and a half year period of the study than those who were not. Further, one of the frequent causes of mortality for those taking sleeping pills seems to be an increased vulnerability to infection, as indications are that induced sleep doesn’t provide the same immune-boosting benefits of natural sleep. It also doesn’t provide the same kind of deep sleep that is so important to overall physical and mental health. The bottom line is that they are truly a very last resort, and best avoided.
The sleep researcher Matthew Walker, who wrote the book ‘Why We Sleep’, writes –
“I was once fond of saying, ’Sleep is the third pillar of good health, alongside diet and exercise.’ I have changed my tune. Sleep is more than a pillar; it is the foundation on which the other two health bastions sit. Take away the bedrock of sleep, or weaken it just a little, and careful eating or physical exercise become less than effective…”
So many people have experienced struggles with their sleep during recent times – and, as we have seen, long before it as well. Yet there are many tactics we can employ and experiment with to try to experience the full benefits sleep provides, and so very many reasons why it is worthwhile trying. Indeed, it is especially important at this time – our economies need innovation, our bodies need strong immune systems, our relationships need grace, and we all need emotional resilience. Sleep is the tonic for so many aspects of our ability to thrive. Let’s do all we can to benefit from the amazing benefits of sleep!
‘Why We Sleep’ by Matthew Walker
‘Sleep’ by Nick Littlehales
‘Sleep Smarter’ by Shawn Stevenson
‘Eat Move Sleep’ by Tom Rath