Turn out the lights.
Richard Stevens used to wonder why there is a higher incidence of breast cancer among women in the industrialized world than in developing countries. Then, “I literally woke up in the middle of the night – there was a street lamp outside the window, and it was so bright that I could almost read in my bedroom – and I thought, Could it be that?”1 Stevens is a cancer epidemiologist who might have discovered a link between cancer and artificial light. The cure, however, might require the assistance of an ancient faith.
For thousands of years, nighttime skies all over the world were largely unlit. Then Thomas Edison produced a reliable, long-lasting light bulb in 1879. Cities began to glow the next year when Wabash, Indiana became the first to be lit solely by electricity. Today, for someone standing on the North Rim of the Grand Canyon on a moonless night, the brightest feature of the sky is not the Milky Way but the glow of Las Vegas, 175 miles away. Using the Bortle Dark-Sky Scale (a nine-level numeric measure of the night sky brightness – class 1 being the darkest skies through class 9 being the brightest), scientists rate the nighttime sky above New York City as Class 9.2 American suburban skies are typically Class 5, 6, or 7. The darkest places in the U.S. are almost never darker than Class 2. Yet this is not a golden glow.
Artificial light appears to disrupt our circadian clock that governs the release of melatonin, a cancer-protective agent. In the early 1980s, The Nurses’ Health Study revealed a strong association between working the night shift and an increased risk of breast cancer. For men, prostate cancer rates in the United States doubled from 1930 to 1992 – paralleling the rise of second shift work. Studies indicate that prostate cancer rates are higher in men who work a second shift. Even the tiny luminous rays from a digital alarm clock can be enough to disrupt the sleep cycle. This artificial light turns off a “neural switch” in the brain within minutes. So how does religion offer a remedy?
For the sake of argument, let’s assume that God did indeed create the world. In so doing, he also ordered it… arranged everything so that human beings would flourish. This ordering included the 24-hour day that begins at sundown, not sunrise. Genesis 1:3 reads: “And there was evening, and there was morning, the first day.” God arranged a world where he prepares our waking hours while we dream sweet dreams. As the Psalmist says: “It’s useless to rise early and go to bed late, and work your worried fingers to the bone. Don’t you know he enjoys giving rest to those he loves?”3
This religious view, however, was contracting while artificial lighting was expanding. The older ordering of “the day” was reversed so that sleep became more of a necessary evil. Napoleon, Louis XIV and Churchill were cited as high achievers who supposedly slept only a few hours each night. Einstein, who required 10 and sometimes even 12 hours of sleep per night, was considered an eccentric. Yet in earlier times, when Christianity shaped our workaday world, diaries from the pre-electric-light-globe Victorian era show adults slept nine to 10 hours a night with periods of rest more in line with seasons of sunrise and sunsets.
The shrinking of sleep continued in the 20th century. The average sleep time for an American declined from 9 hours in 1900 to 7 hours in the 1970s. Today, it’s down to just 6.1 hours, according to a study published in the July 2005 issue in the American Journal of Epidemiology. This is what happens when “the day” is upended and artificial light becomes ubiquitous. Ever add up the hours we burn staring into Blackberries, computer monitors and TV screens that extend our waking hours while shrinking sleep time?
It’s a worthwhile question since, for those of us in the northern hemisphere, we long for December 21st – the Winter solstice. The sun feels like those mercury vapor lamps in a high school gym, slowly warming up. Ah… Yet we might be healthier if we loved the darkness as much as the light. God did order a world with darkness demarcating the first half of the day while we dream sweet dreams.
For those inclined to do more than consider, reordering “the day” is not easy. Workers on second shifts might close the curtains more tightly, turn off all artificial lighting and try sleeping in pitch-black darkness. This is challenging, since I sleep next to a digital alarm clock emitting tiny luminous rays. And my three kids (ages 18, 20 and 24) – they love to stay up all hours of the night. Perhaps they ought to get to bed earlier (now that’s faith!). Or it might be as simple as turning off all those darned nightlights. In any event, I recall that my father used to harp on us to turn out the lights!!! Maybe he had a point.
1David Owen, “The Dark Side: Making War on Light Pollution,” New Yorker magazine, August 20, 2007
2 John E. Bortle created the nine-level numeric scale and published it in the February 2001 edition of Sky & Telescope magazine to help amateur astronomers compare the darkness of observing sites.
3 Psalm 127:2 (The Message)