By Mark DaCosta- Medical researchers have, only recently, begun to understand what happens when humans sleep, and why sleep is important. It has been discovered that natural, adequate, high quality sleep is essential for mental and physical health.
One of the facts that is beginning to emerge from scientific research is that the customs and “ways of life” of humans are changing far more rapidly than the human body is evolving or adapting. And the rate of change is accelerating. The result is an increasingly intense clash between how our bodies function naturally and how we must act if we are to be economically productive and socially accepted. This increasing clash or widening gap – depending on what we call it – may be most obvious in how and when we sleep, and the mental and physical effects of changing external demands that affect our sleeping behaviours.
Some researchers believe that the realities of modern life may be placing psychological and physical stressors on our bodies – particularly sleeping habits – that could result in the deterioration of the quality of our lives.
Before the industrial revolution, which began around 1760, human sleeping habits were different from what they are presently. About the early 1990s, British historian Roger Ekirch conclusively discovered that prior to the revolution most people slept in two phases each night. The first phase began at about 21:00 hours (9 pm). At about 23:00 hours (11 pm) people would wake up, without any external prompting, and go about common wakeful activities such as cooking, eating, reading, praying, and socialising, depending on their particular cultural norms. They would then resume sleeping at about 1 am and awake on the new day at, or near dawn. Ekirch called this pattern biphasic sleep.
Ekirch’s research found references to biphasic sleep patterns dating back to the 8th century BCE. It would therefore appear that biphasic sleep has been the natural human sleeping pattern for thousands of years.
This sleeping pattern changed when the industrial revolution brought with it artificial light. After the advent of gas lighting in the 1700s, and later, electric lights, people began to go to sleep later at night, and to sleep in one long continuous burst, rather than two. This pattern is called monophasic sleep.
In the late 1980s and early 1990s, sleep researcher Thomas Wehr did an experiment in which 15 men consented to participate. The men were placed in a minimal lighted environment with no outside contact, and no way to know whether it was daytime or night. Within a few weeks, the men began to exhibit biphasic sleep. Similar experiments have been repeated many times since then, with identical results. It would seem that biphasic sleep is still the default sleep pattern in humans, and our habit of monophasic sleep is induced by artificial light, and may be considered to be “unnatural.”
Experiments have established that light alters or adjusts our sleep-wake pattern by affecting the internal clock in our brains – the circadian clock. Experiments and observations have also shown that tampering with that internal clock may have negative mental and physical outcomes.
For example, many people who work on a changing shift system – thereby constantly disturbing that internal clock – are known to have higher instances of sleep disorders, personality, mood, eating, and substance abuse issues, as well as physical problems – notably cardiovascular disease and type 2 diabetes. It would appear that life in a modern world is applying health challenges to our bodies for which we may not be prepared.
Experts say that our bodies will eventually adapt to the new demands, but this will take time. Meanwhile, many scientists have been suggesting, for years, that governments, businesses, and the scientific community work together to mitigate the health problems associated with disrupted sleep patterns. Unfortunately, apparently, ironically, scientific findings do not carry much weight in the modern world. As a result, the majority of people are paying the price for the negligence of the few.
