Science confirms what your parents always told you: sleep is important
In a world bursting with new medical discoveries—from ancient herbal treatments to pharmaceutical wonder drugs—it turns out that the best prescription for health may be what you’ve heard all your life: get a good night’s sleep.
Eight hours or so of rest holds great promise not only as a pound of cure, but as many ounces of prevention. Proof! (June 2004), a British alternative health magazine, points to research showing that sleep can be a significant factor in preventing diabetes and cancer. A 10-year study that’s part of the ongoing Nurses’ Health Study found that short sleepers (5 hours or less a night on average) had a 57 percent higher risk of diabetes than people getting eight hours a night. (Curiously, people who sleep more than 9 hours also have a higher risk of the disease.)
Proof! also highlights a Finnish study exploring why flight attendants were more likely to develop breast cancer, which zeroed in on their disrupted sleep patterns. Lack of sleep has been shown to reduces the body’s level of melatonin—a hormone produced by our bodies that has been identified as a powerful cancer-fighting anti-oxidant and also been shown to lower the production of estrogen, which spurs the growth of breast and ovarian tumors.
Healthy operation of our bodies’ hormonal functions, which are increasingly linked to strong immune systems and general vitality, appears to be one of the chief benefits of sufficient sleep.
Yet as science confirms the importance of sleep for staying healthy, many of us are getting less and less of it. “Thirty years ago, adults slept around 7.68 h/night,” reports Proof!. “Eighty years ago, 8.77 h/night was reported by college age adults. Now…the U.S. National Sleep Foundation finds that most adults only sleep an average of 6.85 h/night.”
Outlook ( Feb. 15, 2004), a weekly news magazine from India, calls sleep “the best kept secret in public health,” noting that sleep disorders in the U.S. alone cost the economy $45 billion a year. Dr. Ajit Vigg of the Hyderabad-based Institute of Sleep Medicine reports that “urban Indians now sleep under six hours a day because of changed lifestyles” and Outlook estimates that one-third of all Indians are at risk of injury at work, home or on the roads due to a lack of sleep.
Sleep patterns around the world have undergone a revolution over the past two centuries as the spread of artificial lighting profoundly changed the shape of human lives, first in cities and now even in many remote villages. Throughout most of history sundown brought an end to the activities in most homes, with people crawling into bed soon afterwards.
A. Roger Ekirch—author of a magisterial history of nighttime, At Day’s Close (Norton)— argues that the very nature of a night’s rest has changed since the Industrial Revolution. Sleep for our ancestors was often divided into two shifts of roughly four hours, with a period of wakefulness lasting an hour or longer in between.
A study conducted by the U.S. government’s National Institute of Mental Health appears to confirm Ekrich’s thesis. When people in an experiment were deprived of artificial light throughout the evening and night, they began to exhibit “a pattern of broken slumber—one practically identical to that of pre-industrial households,” Ekirch writes. Researchers in the study, noted hormonal changes in test subjects and “likened this period of wakefulness to something approaching an altered state of consciousness not unlike meditation.”
We still call midnight “the bewitching hour” because pagans in Europe practicing their old religion in defiance of Christian bans secretly performed rituals in this interval between rounds sleep. But Ekrich believes this period of nocturnal time-out-of-time played an important role in the psychic lives of almost everyone as an opportunity to reflect, pray, make love, think about your dreams— contemplative activities which were impossible to pursue during days of long, hard work. Night was the time for inner explorations of spirit and soul. “By turning night into day,” he writes, “modern technology has helped to obstruct our oldest path to the human psyche.”
While it may not be practical for many of us to reclaim the sleep patterns of pre-industrial peoples, we can easily incorporate some elements of this midnight reflection into our lives. Try turning off the lights early, and spending some time alone with our thoughts before going to sleep, or doing that in the morning rather than jumping right out of bed. And if you do experience trouble sleeping, think of the time awake as a gift of contemplation rather than the burden of insomnia.