Experts say that around the world people are sleeping less than they have in the past. Given that sleep is a basic human need, one might reasonably be surprised at the elasticity of people’s sleeping habits. The progression towards less sleep is no small matter. The Center for Disease Control and Prevention has called the trend of sleep deprivation and the associated maladies of fatigue, insomnia, and cognitive impairment a public heath epidemic.
According to authors Michele Ferrara and Luigi De Gennaro in their 2001 review of sleep needs, in the past century humans have reduced their average time spent sleeping by 20 percent. This trend appears to be consistent across different age groups, including the elderly, college students, and children. The American Cancer Society reported that between 1959 and the mid- 1980s people between the ages of 50 and 65 decreased their nightly average amount of time spent sleeping by a full hour (down from 8-8.9 hours to 7-7.9 hours). College students are also reported to sleep for two hours less than they did in the 1980s. Finally, some studies also identify children as sleeping less, but of all the examined demographics they remain perhaps the hardest to study and have yielded the most controversial results.
Research from the 2013 International Bedroom Poll indicates that today people from Japan represents the group that sleeps the least on work nights. Two thirds of Japanese sleep less than seven hours a night, with the average being six hours and 22 minutes. America ranked second in this evaluation—with 53 percent of surveyed participants reporting less than seven hours of sleep on a workday night and their average amount of sleep coming to a total of only six hours and 31 minutes.
There are many possible explanations as to why people around the globe are sleeping less. Certainly one of the biggest causes of change in the modern human’s circadian rhythm stemmed from the advent of artificial light. Artificial light has not only lengthened the number of hours that a person can feasibly work in a day, but has also given individuals unprecedented power over their sleep/waking patterns based on when “lights out” time is determined to be.
Another such hypothesis is that the amount of time people spend sleeping is inversely correlated with the time people spend working. Since 1870, the rise of technology and in particular the industrial revolution has led to dramatic decreases in the number of hours that people in the developed Western world have spent working. However beginning in the 1970s, several nations including the USA have experienced a small but distinct reversal. While this increase in no way approaches the magnitude of the pre-industrial revolution era (during which workers in countries like Australia worked as many as 3,300 hours in a year, or 63 hours a week) it is a trend that is particularly noticeable among higher wage-earners with higher education. Longer work hours of course mean less time spent doing other activities, including sleeping.
Yet another potential cause in the reduction of hours that people spend sleeping is that people have more opportunities for leisure activities that are a higher priority. In an article published earlier in 2014 in the journal Frontiers in Psychology, researchers from the Netherlands examined the phenomena they referred to as “sleep procrastination.” Like other kinds of procrastination, sleep procrastination happens when an individual is fully capable of taking proactive action (going to bed at a decent hour), but continually puts it off in favor of other activities. Easily accessible, passive, and endless sources of entertainment such youtube videos, reading, or playing videogames are no doubt sources of sleep procrastination.
By Sarah Takushi