The importance of a good night’s sleep is undervalued in today’s society. But research suggests it’s far more important than we give it credit for.
What if we valued the time we spent sleeping just as much as our waking hours? Imagine a world with sensible schedules, later school start times and no daylight savings? How about well-designed biologically responsible, amber street lights instead of intensely bright, white LEDs which ruin restorative rest?
What if sleep hygiene was rewarded, naps encouraged, exposure to sunshine prescribed, and medical treatment and lifestyle choices tailored to an individual’s chronotype? (Our chronotype determines when we’re most alert and energetic, and when we prefer to sleep. For example, a lark, an owl, or in between.)
A healthier reality is possible but it involves more appreciation of sleep, greater awareness of the impact of light on biology, as well as a deeper respect for the natural cycles we depend upon to maintain health, happiness and wellbeing.
While a third of our life is taken up by sleep, indicating its importance, it says a great deal about our culture, that compared to other areas of research, sleep still has many secrets.
Thankfully, attitudes are improving and interest in chronobiology (the study of circadian cycles) is surging as we learn more, it’s obvious sleep isn’t just a pillar of health like nourishing food and exercise. Rather, sleep is the bedrock upon which everything else rests.
Of course, this has many profound implications for us as individuals and society as a whole. Every cell in the body has its own regulatory biological clock but, until recently, we didn’t understand how they worked.
When scientists finally unlocked the mechanism, their significant breakthrough was awarded the Nobel prize in 2017, and justifiably so. It turns out the body clock is one of the most underrated forces in our behaviour.
Humans evolved to use day and night as cues to regulate physiology and, by default. We have an exquisite sensitivity to light, and an equally complex and sophisticated wake/sleep cycle.
Simply put, sleep is non-negotiable and we’d be wise to accept this because research links a lack of sleep to DNA damage, weakened immunity, increased sensitivity to pain, reduced healing time, lowered testosterone and libido in both sexes, as well as to illnesses including depression, heart diseases, obesity, metabolic syndrome and cancer.
Associate Professor Sean Cain, a psychology researcher at Monash University, explains, “Almost every tissue in the body has circadian rhythms, and when they are disturbed, the whole system starts to fall apart.”
Furthermore, unlike the rest of the body which relies upon the lymphatic system to remove metabolic waste, the brain has its own singular system.
Cerebral spinal fluid surrounding the brain repurposes blood vessels to flush through the organ to carry away metabolic waste. This crucial clearing process only happens in a sleeping brain.
There are also genes in the brain associated with metabolism, restoration and repair that are solely turned on during slow-wave sleep (SWS).
In an ironic twist, SWS depends upon sufficient vitamin D levels, and many of us today are deficient because we avoid sunshine, wear sunscreen, and spend an inordinate amount of time indoors. Without question, sleep is the best healing agent there is – far more potent and effective than medication. Plus, it’s free from unwanted risks and side effects.
Yet, humans are the only species to willingly deny rest and there’s no evolutionary buffer available that lets us accumulate a debt in sleep and somehow pay it off later. In reality, sleep deprivation costs the economy billions in lost productivity, illness and mishaps every year. When tried, reaction time slows, decision making is impaired, judgement off, the mood disturbed, and we’re more accident-prone and impulsive. Then to counteract the physical pressure to rest, we crave stimulants and depend upon them to get through the day.
This leads to another misconception. Sleeping in one consolidated eight-hour block is a modern-day invention, brought about by the industrial age and artificial light at night. The truth be told, consolidated sleep actually robs us of calm and other benefits.
Our slumber, before artificial light became mainstream, was very different. In a world illuminated by fire, we once experienced segmented sleep, where we fell asleep a few hours after dark, woke in the night for a few hours, and then slept again until dawn.
As the industrial age took over, as did the use of mechanical clocks and artificial light, segmented sleep was nearly forgotten about. Fortunately, sleep researcher Thomas Wehr and historian A. Roger Ekirche have reminded us. Intriguingly, it isn’t just the sleeping pattern that’s dissimilar. Something extraordinary happens to the body and state of mind during segmented sleep. The period of wakefulness between sleep (once called night walking or the ‘hour of God’) was a sacred time of prayer, reflection and creativity. So, what was it that made this time so special?
Well, the term, ‘hour of God’ gives some indication. Wehr determined that, unlike consolidated sleep, the hormone prolactin continues to be produced during the period of “quiet wakefulness.” This results in unusual serenity, calm and mental clarity. With a fully rested brain, we wake gently and naturally when we’re meant to and our days can be spent in a state of true wakefulness.
Sadly it’s all too common today, to wake in the night feeling anxious, experience bouts of insomnia, and when sleep does occur, it’s typical to be startled awake by an alarm clock, and then feel slightly hazy all day. Although a brain blissfully bathed in prolactin may be out of reach for most, there’s still much to be gained from rejuvenating repose each night.
The best sleep occurs in complete darkness because even when the eyes are closed, the body detects light, especially shortwave blue light, the kind present in daylight.
In summary, sleep is not an indulgence, nor is it a waste of time, or a sinful sign of moral lassitude and physical laziness. Truly, it is so crucial, mysterious, and special, sleep should be sacrosanct.
- Spend time outside, especially in the morning as this helps encourage sleep at night.
- Top up vitamin D with sensible sunlight exposure, and in winter, supplement with cod liver oil.
- Nourish your gut microbiome via wholesome, fresh, seasonal, organic food.
- Avoid late meals and snacking at night.
- Favour light sources with a CCT of 1800-2000k (similar to fire or candlelight) and keep lighting soft, indirect and position it low.
- Stock up on 60-watt incandescent lightbulbs and use them with discretion.
- Prioritise relaxing, calming activities in the evening to get the body bed-ready.
- Before bed, turn off the modem and leave digital devices out of sleeping quarters.
- Keep bathroom lighting dim, and if you need to get up in the night use a soft red nightlight.
- Ensure the bedroom is pitch black. Remove or cover any source of light, including devices with the smallest LED. If this isn’t possible, a good eye mask will suffice.