You might not think much of only getting six hours of sleep each night, but according to research recently published by RAND Europe, sleep debt costs the UK economy an eye-watering £40 billion per year - that's almost 2% of the UK's GDP (gross domestic product). Still, that's better than the US at 2.28% or Japan at 2.92% of GDP.
At this point, there are likely to be (at least) three categories of reader:
Category one: the ones for whom sleep is a priority, and who ensure that they regularly get the recommended amount of shut-eye and don't have any trouble falling asleep
Category two: the ones that are all too aware that they aren't getting enough sleep and are desperate to get more, but can't.
Category three: the ones that don't believe sleep is important, or, at least, not as important as living life to the full or working into the early hours to make a positive impression at work.
I am fortunate/boring enough to fall into category one. However, I know plenty of people who fall into categories two and three.
For those in category three, that forgo getting enough sleep out of choice, I am hoping this blog may at least get them to ponder that choice a little more carefully. For those in category two, scroll to the bottom, for a few tips ton how to get a better night's sleep.
Drunk on the job
One of my favourite research papers on the subject of sleep, is one that dates back to 2004. The sleep deprivation study in question, published in the Journal Sleep, took 48 adults and restricted their sleep to a maximum of four, six or eight hours a night, for two weeks. In addition, one lucky/unlucky group was deprived of sleep for three days straight!
Unsurprisingly, those who slept for eight hours each night, had the highest performance, on average. Those who got only four hours a night did progressively worse each day. The group that got six hours' sleep seemed to hold their own, until around day 10 of the study, after which their performance plummeted and was equivalent to the group that had not slept for two days straight. Most worryingly of all, they believed their performance hadn't been affected; yet, it was the equivalent of them being mildly inebriated.
Whilst we may be oblivious to the impact that sleeping 6 hours or less is having on us, it doesn't mean it isn't jeopardising our performance or our career prospects.
Sleep yourself slim
A number of more recent studies, have found that levels of ghrelin (the hunger hormone) were higher (and leptin - the hormone that lets us know we're full - lower) in those that didn't get enough sleep. The studies found that those forced to shorten their sleep cycle, craved high fat or carbohydrate laden foods later at night, and they ate more than people who slept longer.
Studies have also shown a positive correlation between our metabolism rate and the amount of sleep we get. Not sleeping enough not only slows our metabolism (meaning we burn fewer calories each day) but it increases how hungry we are, meaning we are likely to eat more later at night, increasing our risk of piling on the pounds. A good night's sleep ensures the proper regulation of hormones in he body. Multiple studies have linked poor sleep to an increased risk of obesity and type 2 diabetes.
Other outcomes associated with poor sleep
Those who regularly get less than six hours' sleep each night have a 13% higher mortality risk, compared to those who get between 7 and 9 hours each night. Lack of sleep and lack of good quality sleep, stunts productivity at work and increases fatigue, which means you will be less productive and more likely to make mistakes - and arguably less likely to get promoted. Lack of sleep also impacts our mood and has been linked to increased rates of depression. It has also been shown to compromise our immune function, which has been linked to higher rates of cardio vascular disease, as well as certain types of cancer.
A number of recent studies have suggested a link between Alzheimer's and amyloid-beta protein build up, accumulating into plaque. Currently the evidence is circumstantial, but researchers believe there is a link, as those suffering from Alzheimer's show high levels of plaque build up in the brain. Regular, good quality sleep, lasting between 7-9 hours helps clear plaque.
Why is sleep important?
Poor sleep can have adverse effects on our health, but we shouldn't forget just how important sleep is in rejuvenating our body and our mind. Just the other day, new research was published on the beneficial effects of sleep. This time the research was focussed on the shortening of synapses. Whilst that may sound bad, it is actually a good thing, as researchers believe it aids memory consolidation and helps us forget unimportant information accumulated the preceding day. Sleep also clears the brain of toxins, which it is unable to do effectively when we are awake. It also helps us grow muscle and repair tissue.
How to get a good night's sleep
Getting enough sleep can be as simple as allocating enough time for it; prioritising sleep over other activities. However, for those who are simply unable to sleep, perhaps due to stress or a digital addiction, below we have listed a couple of tips which you may find useful:
Meditate: incorporating practices such as meditation or mindfulness into your life can help the mind switch off from life's worries, helping you to get a good night's sleep. Even 5-10 minutes a day can make a noticeable difference.
Exercise: psychological stress can result in elevated levels of circulating cortisol, that can disrupt sleep and leave you lying in bed thinking about work and other worries. Exercising helps lower circulating cortisol, which means you'll sleep much better. However, try not to exercise within two hours of bedtime, as exercise does increase cortisol levels temporarily, which may impact your ability to fall asleep.
Avoid stimulants: most people know not to drink coffee after 2pm, as it risks impacting their sleep. The same goes for energy drinks. Alcohol, on the other hand, may help you get to sleep quicker, but the quality of sleep is likely to be much poorer and you may even wake up much sooner, leaving you feeling lethargic the next day.
Avoid technology before bed: using devices, such as mobile phones, that emit blue light can inhibit the production of melatonin, which would normally signal to the body that it's time to sleep. Past studies have shown that blue light in the early evening causes a circadian delay, or resets the clock to a later schedule, potentially limiting the amount of REM sleep we achieve. Try curbing the use of blue light emitting devices within an hour or two of bedtime - it will make it easier to fall asleep.
Stick to a routine: sticking to a routine when it comes to sleep is important. Research has shown that irregular sleeping habits, such as playing catch-up at the weekend, can affect our circadian rhythm, making it more difficult to fall asleep consistently each night.
Don't stress about it: If you don't get a good night's sleep, there's little point stressing about it, as it will likely just make things worse. Easier said than done perhaps, but give yourself a break. Try and figure out what went wrong and think about what you can do differently next time.
For those that have young children, it gets a little trickier, but it's not impossible. Working as a team is crucial; taking it in shifts to enable each parent to get some semblance of sleep. Once they are a little older, routine is crucial, as is restricting the use of technology before bedtime.
If you have any questions or are interested in running a sleep workshop at your organisation (or even introducing 1-2-1 sleep coaching sessions for employees), our clinical psychologists are on hand to help. Simply get in touch: firstname.lastname@example.org | 0207 993 4402