Sleep: when it’s just not happening

Did you know that the World Health Organisation has declared a sleep loss epidemic across developed nations? Two-thirds of adults in the US, Europe, Japan & South Korea fail to obtain the recommended 8 hours of sleep per night.

Why does it matter?

Thinking about your own habits, this may not surprise you, but did you know that routinely getting less than 6-7 hours’ sleep a night drives a hole through your immune system, increases your risk for Alzheimer’s disease, cancer, diabetes, cardiovascular disease, stroke. It also disrupts hormone levels and your ability to regulate food intake. If you don’t sleep well, you’re more likely to gain unwanted weight.

It affects fertility. Sleep-deprived men have lower testosterone levels and sperm counts. Women with disrupted sleep are more likely to have disrupted menstrual cycles. & as nature is very tricksy, as a signal of our relative infertility when poorly rested, we are perceived as less attractive when we don’t get enough sleep. Put bluntly, you are less likely to get laid when you’re under-slept as somewhere in your beloved’s brain, the signal is being received that you’re poor mating material!

It also impacts upon our mental function. Our memory is decimated, performance & judgement impaired; we become more reckless and irrational, less empathetic and more prone to anger. Not surprisingly, lack of sleep also destroys our energy levels. Did you know that car accidents caused by driving whilst tired, outnumber those from drinks & drugs combined??

Why does lack of sleep have such a devastating impact upon our health?

Most of you will be aware of your circadian rhythm – that internal 24-hour clock that determines the sleep-wake cycle. You will also be familiar with melatonin, the hormone responsible for signalling to us that it’s night-time & we should therefore be winding down to bed.

It’s a misconception that melatonin actually drives sleep. It doesn’t. A chemical called adenosine is responsible for that. This compound builds up in your brain with every moment that you are awake & eventually hits a level that creates an irresistible urge to sleep. Once you succumb the brain can start the process of clearing out the adenosine & after approximately 8 hours it will have completed the task & you will be alert, ready for another day’s activity & the cycle begins again.

In addition, 

If you sleep for less than 8 hours some quantity of adenosine will remain and you will carry that balance forward into the next day & the next with the sleep deficit contributing to fatigue that you may even fail to recognise as anything other than ‘normal’.

A chronic sleep deficit can also result in chronic stress response activation. With that comes elevated blood pressure and an absence of the rest & repair hormones which ordinarily maintain the integrity of your blood vessels. This is no hypothetical risk of cardiovascular disease – it is a measurable phenomenon that each spring when the clocks go forward an hour & we lose an hour’s sleep, there is a spike in heart attacks the following day. The numbers noticeably drop in the autumn when we gain an hour’s rest.

Lack of sleep is similarly implicated in development of another chronic disease – type 2 diabetes. Our cells are noticeably less responsive to the effects of insulin when our sleep is limited

If we’re not sleeping enough, it stands to reason that we’re in dream deficit too. 

What does this mean in practice & does it really matter?

The sleep phases in which we dream – REM sleep – are the only times in a 24 hour period when there is zero noradrenaline in our brains. Noradrenaline is the brain equivalent of stress hormone adrenaline. It is suggested that having these ‘stress-less’ phases enables us to safely process the more emotional or traumatic periods of our lives. Certainly, some evidence has proposed that dreaming about them enables us to ‘neutralise’ our more troubling experiences, thus making their memory more tolerable & offering some credence to the notion of ‘sleeping on it’*.

REM sleep also appears to be crucial in enabling us to navigate the social world. Deprived of REM sleep we lose our faculty for deciphering the emotions & intents of our fellow humans. We cannot accurately ‘read’ their expressions & thus start to perceive the world as being an alien, threatening place where benign gestures become intimidating. You may extrapolate the impact on social harmony of a sleep deprived population. Similarly, at a micro level, also perhaps discern the origins of an absence of ‘bedside manner’ in a sleep-deprived A&E professional, or the sociopathic reputation of the ‘sleep is for wimps’ CEO?

Finally, on the subject of dreams, did you know that if we persist in restricting our sleep and hence our dreams, they may start to force their way into our consciousness in the form of hallucinations??!!

It seems clear that one of the functions of sleep is to enable dreaming even though we’re not sure exactly why it’s so beneficial.

*this theory regrettably does not appear to bear out in cases of PTSD.

Strategies to support a restful night’s sleep

1) Get exposure to morning sunlight. Getting outdoors during the day is crucial to regulation of the sleep/wake cycle.

2) Limit artificial light exposure after dark. I’m not suggesting that we all return to firelight only, but use your dimmer switch or mood lighting. Candlelight is great if that floats your boat.

3) Please, please limit your exposure to the blue LED light of electronic devices. Ideally switch off a couple of hours before bed & return to reading paper rather than a screen.

4) Keep regular hours, even at weekends. This could well be the most important piece of advice as we struggle to adapt to changes in our sleep routine.

5) Don’t rely on alcohol. A glass of wine acts as a sedative on the nervous system which may help us to drop off, but a) it’s a stimulator of the stress response & b) it robs us of deep sleep & may disrupt our breathing, further impacting upon the quality of our sleep.

6) Take some exercise during the day – this is associated with improved quality sleep. But use your evenings to wind down & avoid the gym etc 2-3 hours before bedtime.

7) Invest in some blackout curtains for the bedroom. & turn the thermostat down. Our core temperature naturally drops during sleep & an overheated bedroom will inhibit your ability to drop off.

8) Avoid a high sugar/refined carb meal in the evening as these are associated with lower quality sleep.

9) Avoid caffeine (obvs!). Caffeine blocks the adenosine (remember that?) receptors and renders us unable to sleep until we have successfully metabolised it.

10) Don’t nap in the afternoon.

11) Perhaps consider an evening bath – adding magnesium salts provides a calming element, as does low lighting, chilled out music, diffused essential oils etc, etc

12) If you still struggle to sleep after all this, don’t lie there. After 20 minutes or so, get up, sit in another room in dimmed lighting & perhaps read or listen to music until you start to feel tired. Then return to your bed.