There is tons more data around the way in which sleep affects our body, with the above simply scratching the surface. For example, let's look at the cardiovascular system - a 2011 study of more than half a million men and women shows that shorter sleep was associated with a 45% increased risk of developing coronary heart disease within 7-25 years of the study. In another study over 14 years, those sleeping 6 hours or less were 400-500% more likely to suffer a cardiac arrest than those who slept for longer. Adults 45+ who sleep fewer than 6 hours a night are 200% more likely to suffer a heart attack or stroke in their lifetime - truly alarming stuff.
Given that diabetes now is considered an epidemic, it's interesting that lack of sleep has now shown increased rates of type 2 Diabetes in two seperate and large independant studies. This is interesting but doesn't prove a true link - so further studies were conducted. Healthy participants with no issues with blood sugar were limited to sleeping just 4 hours a night for 6 nights. By the end of the study participants were 40% less effective at absorbing a standard rate of glucose. To put this into persepective, if you presented at your GPs office with similar blood sugar readings you'd be classified as pre-diabetic.
Lack of sleep also decimates your immune system. Studies have shown clear, lineal relationship with infection rate of the cold virus and sleep. In those sleeping an average of 5 hours per night, infection rates were almost 50%, yet in those with 7 hours or more this dropped to just 18% It also affects your antibody rate should you decide to get a vaccination for flu for example. One study showed that patients who had 7 or more hours of sleep showed a powerful antibody reaction to a flu shot, yet this dropped by more than 50% for those who only had 4 hours. Even more shocking is that one landmark study at the University of California demonstrated that a single night of just 4 hours sleep caused a decrease of natural killer cells by 70%.
So what about our minds? Well I'm afraid I don't have good news here either.
Alzheimers is tipped to be the next health epidemic with rates expected to triple worldwide by 2050. Alzhiemers is associated with a build up of a protein called beta-amyloid which forms plaques known as Amyloid plaques in the frontal lobe.
Within the last 10 years there has been an amazing discovery about our brains, Dr Maiken Nedergaard discovered there is a system called the glymphatic system made up of glia cells throughout the brain. This system acts like a cleaning system in that it collects and removes metabolic contaminants created by neurons as they do the work they do, day in day out. Whilst this system is active when we are awake, it operates at a much higher level when we sleep. Once we enter deep NREM sleep we are effectively treated to the equivalent of a brain deep clean. Glial cells shrink in size by up to 60% and cerebrospinal fluid can move more freely to clean away all the unneeded waste from neural activity. As if that wasn't enough, it also remarkably is able to remove amyloid protein from the brain. There are now many who believe that improving your quality of sleep now could in fact reduce your risk of developing Alzheimers in the future.
One very important thing we should consider given our roles is how lack of sleep could effect us day to day. One area even the smallest lack of sleep hugely affects all of us is concentration. Every single hour in the US someone dies in a traffic accident as a result of a fatigue related error. Many people think this is caused by falling asleep at the wheel, which actually happens infrequently. The more common is a lapse in concentration called a microsleep. These last only a few seconds, and are suffered by individuals who routinely sleep less than 7 hours a night - I'd guess at that being a huge amount of the drivers on our roads. Most of us have no awareness of actually having a microsleep, but when you do, momentarily you lose decisive control. A 2 second microsleep can drift you into oncoming traffic; do this at 70 mph and it could be game over.
In a truly worrying study in Australia, researchers took two groups - one they got drunk to the legal driving limit, the other they sleep deprived for one night. They both performed concentration tests and those who had been sleep deprived were as cognatively impaired as those who were legally drunk.
Drowsy driving can be truly catastrophic. Driving after just 5 hours sleep you are 3 times more likely to crash, reduce that to just 4 hours sleep and you are 11.5 times more likely.
I could go on with more (depressing) information, but by now I'm sure you get the point. Sleep is vitally important for us all, much more so than I have even cared to consider. So what can you do about it? Here's a few things I've implemented that are helping me massively, some may sound 'boring' but if you've ever suffered insomnia for more than a night or two, you'll try almost anything.
- Try to go to bed around the same time every day, and get up at around the same time every day (including weekends). This should help your body to establish a sleep pattern. Sleeping late on weekends doesnt make up for a weeks worth of short sleep, but if you do enjoy a lie in (I know I do) try to make it no more than an hour later than your normal wake time.
- Set a screen shut off time. Mobile devices, laptops etc emit blue light which supresses melatonin making it harder to fall asleep. If you have an iPhone consider turning on 'Nightshift' which reduces the amount of blue light during the evenings. If you must use your laptop after dark consider running f.lux in the background. This free programme will again reduce the blue light making the screen look somewhat orange at night. Its weird at first but it works. Keep phones away from the bed if you can't resist that late night scroll through social media. Social media is a known cause of anxiety for many and also keeps us addicted through random reward conditioning, meaning that quick look often lasts 20 minutes.
- Limit caffeine if you can. I love caffeine personally and although I've successfully quit it several times, I just love a cuppa. Caffeine does however have a half life of around 5-6 hours, so I tend to stop drinking it and switch to water after 5-6pm. Decaf often only contains 20% less caffeine so often this isn't all that helpful.
- Carve out time to relax before bed. Reading or listening to calm music can be very helpful. I've personally started turning the TV off if there's nothing I want to watch (I was guilty of watching any old rubbish just because it was on in the past) and reading, and it's been truly transformative to my evenings. I seem to fall asleep far quicker and even look forward to that time to go and read. Reading is said to reduce stress levels by 68% and reading for just six minutes has even been found to reduce heart rate. I've found I get just as many benefits reading ficton or non fiction so you might even learn something new! Paper is best though, one study found reading from an iPad vs paper book at night suppressed melatonin by 50% and reduced significant amounts of REM sleep.
- Try to make your bedroom a sleep sanctuary. Try to make it as dark as possible and invest in black out curtains if you need them. It's also best to be kept on the cool side, if the room is too warm it's harder to sleep - a lower temperature will help you to feel drowsy. A temperature of no more than 18 degrees but higher than 12.5 degrees is usually good for most people.
- Avoid alcohol. Alcohol seems on the surface like it might help, but its merely a sedative. It also fragments sleep meaning you awake momentarily many times throughout the night, even if you don't remember doing so. It keeps you in only the lighter stages of sleep and powerfully supresses REM sleep.
- Exercise - but early in the day. Studies have shown that even just 10 minutes of exercise completed early in the morning can aid falling asleep at night, don't do it late at night though or you might find it harder to drift off. If you can exercise outside this is helpful too as getting daylight early in the morning can help circadian rhythm.
- The last thing I've found incredibly helpful is the Phillips Hue system I splashed out on a little while ago. At night the lights are set to very warm colours with as little blue light as possible, I also dim them as much as I can especially in non task areas like a hallway. I also use the sunset feature on my bedside lamps - This works similarly to Lumie light alarm clocks you may know of. Over a period of 15-60 minutes (as set by the user, I use the 45 mins option) the lights gradually fade to emulate a sunset. This sounds bonkers but it really does work, you aren't aware of them fading until you feel really quite sleepy and it's becoming challenging to read. In the morning they can be set to a cool, ever so slightly blue light - this can help you feel more awake and aid concentration.