Source: Het Nieuwsblad 5-10-2004
Why do we actually still sleep? Of all primates, the human being already sleeps least. Did, a century ago, Thomas Edison not contend that with the invention of electricity and artificial light, sleeping in fact becomes unnecessary? Indeed, having to go to sleep because it is too dark to go out hunting safely or to gather food, today for most people belongs to the past.

In fact, artificial light makes it possible to have factories work day and night in 3 shifts, to have shops open 24 hours a day, to have a dazzling nightlife and even to do all kinds of interesting things at home at night and not to have to sleep. Indeed, why do we actually still sleep?

Why do we “lose” 1/3 of our lives to something that is like “being death”?
Do we really enjoy that so much?

2. Evolution history

Nevertheless, there is something that forces us to sleep. Is it the tiredness of our muscles and mind that creates the need for sleep? Or do our genes in a circadian 24 hours rhythm order us to go to sleep right now? Science has no straightforward answer yet.

As Homo Sapiens we have had a long evolution history. Today we still have the body of the hunter-gatherer, including the coccyx. From a long time before the first Homo Habilis until recently, the human being was extremely vulnerable when it grew dark.
He lived solitarily or in group, but had to remain observant at all times. When he slept, he hided and protected himself as much as possible in caves or on higher places where the entrance or entry could be watched over. As our ancestors were occupied with keeping up a fire, watching and other survival activities, they subconsciously felt it was not permitted to sleep through for several hours a day. Their nights were interrupted several times by active moments. Today, primitive population groups still sleep several successive short sleeps at night. By organizing themselves into groups and hierarchies, the night watch could be reduced to a restricted group and the others could slowly evolve into the modern social sleep, in which the shorter sleeps are linked up and people sleep through, preferably without waking up in between.

3. Sleeping habits

SLEEP WELL

In the Western world, we indeed mostly sleep a sleep that consists of 5 stages that are in turn divided in different phases. When studying sleep behavior outside the European continent and during many study tours, I found that many population groups still have quite different sleeping habits.

The distinctive feature of their sleep behavior is that population groups that still live very close to nature, do not sleep “through” the night, but actively interrupt their sleep. It was also found that the climate is as important as darkness when it comes to explaining the widespread “afternoon nap”. Even in China, most factories and offices are closed down at noon. In Japan, it is still very popular to have a nap behind your desk at noon. At 5 o’clock in the morning, Bombay already shimmers with activity and the inhabitants of Abidjan only get the hang of things at 11 o’clock in the evening.

4. Where you sleep

Not everyone sleeps out his sleeping needs in the same way; frequent shorter sleeps on the ground, a couch, a seat or a bed spread over the entire day are more common than our modern social sleep in a neatly made-up bed from 11 o’clock in the evening till 7 o’clock in the morning. In the Western world, we evolved from sleepers in a nest or cave to more protected rooms or turret rooms, where people and families sat around a fire and looked for the warmth and protection of one another. They slept on beds that protected them against moisture, cold and vermin. These beds mainly consisted of skins, bags filled with all kinds of elastic materials and blankets that were even spread out over the chest with the most precious belongings.
The Greeks and Romans lived and ate on their beds. In the Middle Ages, the most combative slept sitting in full battle regalia to be able to swing into action while naked men, women and children cozily dived in a bed under the skins. Victorian prudery and new ideas on hygiene brought nightclothes, nightcaps, individual bedrooms and beds. French kings received their subjects while half-sitting/half-lying in their beds.

5. How you sleep

Today, 70% of the people still sleep together with someone else and some hundred years ago the Western world adopted the habit of sleeping in individual bedrooms where parents and children can retire.

Since the invention of the metal spring mattress and the bed box, we sleep completely horizontally and the hassock-pillows have gradually made way for modern more or less hygienically sound beds.

6. Women sleep on their sides, men sleep on their fronts or sides

SLEEP WELL

A survey conducted in 1996 amongst 2,000 of my customers showed that 78% of the women are slide sleepers, while 72% of the men are side/belly sleepers. That’s only logical as in earlier days, most women were constantly pregnant and therefore had not many options left. In addition, by lying on their sides, women were able to better protect the fetus.

In fact, men are better protected by their backs and they can get up much more rapidly from the side/belly position. Other studies reveal that 15% sleep on their backs, 24% on their left sides, 47% on their right sides and 14% on their bellies.

But when we lie down, we often lie on our backs. This change is not only caused by mattresses that are much too hard and thus disturb our sleep profile, but also results from the introduction of electrically sit adjustable bed bases that brought King Television even into the bedroom. We now have light, digitalized communication, a worldwide information network… at our disposal 24 hours a day. And at night too, we permanently have access to all kinds of amusement and recreation… even in our bedroom.

We work and travel at night and yet feel that we so build up some kind of sleep debt. Perhaps we indeed can function 24 hours a day without losing much time to sleeping. When comparing the technological changes over the last century to our overall evolution, they took place in a symbolic second, while our body took 30,000 years to evolve from the homo sapiens into modern man.

Since the light bulb was invented in 1936, we technically can handle night work, our lives can become more and more hectic and we can even gather information or find entertainment in the middle of the night.

8. The great lack of sleep

But, how flexible is our sleep need? Do we really just waste one third of our lives? The more I learn about sleeping, the more I realize that the problems we face today are rather due to a sleep deficiency than to a waste of time through sleeping. For one thing bad-sleeping is the worst ailment of our times, and for another thing modern, technological society and higher life expectancy just require that we, even more than in the past, optimally utilize our sleep.

In sleep labs all over the world, sleep debt was created under lab conditions and the behavior of test subjects was studied.Each study shows that even the slightest sleep deficiency has us function less efficiently. For that matter, short naps in the daytime resulting from this sleep deficiency actually are the biggest cause of accidents, both at work and on the road.

So, what is it that makes sleep so important? That is what you should know!

GREEN SLEEP