Given our fast-paced lifestyles packed with activities, sleep deprivation is often mentioned as one of the ills societies are exposing themselves to. A new study, on the other hand, questions whether we are really lacking adequate sleep; perhaps, the real issue has to do with darkness-deprivation.
The researchers of the new study, led by Jerome Siegel from UCLA, compared sleeping habits in the industrialised world with those in 3 preindustrial populations – 2 in Africa and 1 in South America – who live without electricity.
The findings show that the latter spend an average of 7 – 8.5 hours every night trying to find sleep. Only 5.5 – 7 hours are confirmed as sleep time. These figures are similar to those reported by the majority of Europeans and Americans. While this amount of time spent sleeping is generally regarded as inadequate for the health, the researchers of the study suggest 5.5 – 7 hours of sleep might be natural. What is the problem, then?
The researchers also found that the people only slept several hours after sunset. The two groups also woke up at around sunrise. However, while changes in temperatures affected the time of awakening in the preindustrial populations, their counterparts experienced minimal temperature fluctuations in their bedrooms.
Another difference that was revealed entailed interspersedly waking up during the sleep hours. This suggests that compacted sleep might not be ideal.
The greatest difference between the two is recorded in terms of light and darkness: people living without electricity are exposed to darkness for 11 to 12 hours per night while the others have only about 7 hours in the dark. Nighttime physiology can be delayed or switched off by electric light while light from wood or flame cannot. Sadly, the researchers did not evaluate the quality of sleep with respect to this aspect. But, the excess light (or, lack of darkness) being unnatural might be detrimental to us.
It is believed that we have gradually developed unhealthy sleep habits as the world has changed into its modern version. The blue light from smartphones is growing more notorious as studies are revealing its possible harmful effects. Another issue is that even when sleeping, people are not completely in the dark.
Therefore, even if the two groups of people were having the same amount of time sleeping, the quality of the sleep might differ greatly. And, the question remains: are we sleep-deprived, or darkness-deprived? Perhaps, darkness is a luxury we can no more afford in a world where we depend heavily on electricity, and smartphones, and laptops?