When life gets busy, often the first thing we sacrifice is sleep. We’re racing to finish that project for work, so we rise an hour earlier than usual. Or we retire a little later each night as we squeeze in some late-night chores. We know sleep is important, but how much can it hurt if we cut back a little in the name of productivity?
A lot. In fact, it turns out that adequate sleep and peak productivity go hand in hand. That’s because proper rest improves our ability to concentrate, learn, remember, and to better manage busy, stressful times. It’s essential to proper immune function and general good health (and what busy person has time to get sick?). What’s more, research has shown that getting enough sleep can curb obesity, anxiety and depression — it even helps regulate blood pressure.
Sleep is an essential priority, not something we should fit in when we can. Getting enough of it can feel like a luxury in our fast-paced lives, but, really, it’s a necessity for surviving — and thriving — in hectic times.
Some muscles in the body can restore themselves by relaxing between activities; the brain isn’t one of them. It needs more than simple inactivity to function properly — it needs the restorative effects of sleep.
A 2000 study by researchers at the University of California, San Diego, published in the journal Nature, found that the region of the brain responsible for verbal learning was active in properly rested study participants and inactive in sleep-deprived subjects. But the region of the brain associated with memory, called the parietal region, kicked in when sleep-deprived participants took part in the verbal-learning exercises, indicating that the brain can help compensate for its sleep-deprived deficiencies by getting other regions of the brain to “cover” for the affected region.
When this occurs, though, overall brain functioning suffers — and not just minimally. Researchers in Australia and New Zealand, for example, have found that drivers who had been awake for 17 to 19 hours before getting behind the wheel performed worse than drivers with a blood-alcohol level of 0.05 percent.
Lack of sleep also affects mood. Kathy Sexton-Radek, PhD, a clinical psychologist and professor of psychology at Elmhurst College in Elmhurst, Ill., estimates that lack of sleep contributes to depression and anxiety in nearly 40 percent of the patients she sees.
“You need to regard sleep as an investment you’re making in yourself, rather than something you have to do or something you think of as downtime,” she says.
While you slumber, your body is far from idle. During sleep, the body produces cytokines, cellular hormones that help your immune system fight infections. Sleep also promotes the production of human growth hormone (HGH), which repairs muscle and tissue. Missing shuteye, says sleep specialist Peter Freebeck, MD, decreases physical endurance and increases baseline heart rate.
An ongoing study at Stanford University is comparing well-rested college athletes with their comparatively sleep-deprived teammates. In every sport, from basketball to swimming, the athletes getting more sleep are significantly improving their performance, says psychiatry professor William Dement, MD, PhD, founder of the world’s first sleep lab. The athletes also reported increased energy and improved mood.
Getting enough sleep is an essential element of achieving and maintaining a proper weight. In the book Lights Out: Sleep, Sugar and Survival (Simon and Schuster, 2000), T. S. Wiley and Bent Formby, PhD, describe “at least 10 different hormones, as well as many more neurotransmitters in the brain, that go sideways when you don’t sleep enough.” Among these are leptin, which regulates metabolism and appetite, and melatonin, an antioxidant. These hormonal changes can lead to obesity and diabetes. (See “Getting to Sleep” in the November 2004 archives.)
Sleep might also be one of the keys to living healthier, longer. A 2003 study by Finnish researchers surveyed 1,600 adults, ages 36 to 50, in Tampere, Finland, about their sleep habits and health. As Dement and Christopher Vaughan report in their book, The Promise of Sleep: A Pioneer in Sleep Medicine Explores the Vital Connection Between Health, Happiness and a Good Night’s Sleep (Dell, 2000), the results are unequivocal: “Compared to good sleepers, male poor sleepers were 6.5 times more likely to have health problems, and female poor sleepers were 3.5 times more likely to have health problems.”
Sleep specialists stress the importance of respecting the body’s natural clock, or circadian rhythm, which influences alertness, temperature and hormones throughout the day. Although your circadian rhythm is genetically set, a regular sleep pattern can retrain your body’s clock for sleeping and waking times that fit your schedule. The consistency will also help you fall asleep and wake up more easily, says Freebeck. He recommends going to bed and waking up within an hour of a set time every day, including weekends.
Getting regular, consecutive hours of sleep also matters. Your sleep occurs in five stages, ranging from lightest to deepest within 90- to 110-minute cycles. The first part of the night features deeper stages that rest the brain. Early-morning hours are heavier in rapid eye movement (REM), or the dream state, when the body is more relaxed. Since different processes occur throughout the night, it’s best to string together, uninterrupted, four to six cycles, or seven to nine hours. Each of these cycles is equally important, Freebeck says, because the first hours rejuvenate the brain and the last hours help the body recover.
To begin to get more sleep, tack on 15 minutes of shuteye each night for a week, suggests New York University professor of medicine Joyce Walsleben, RN, PhD, a member of the NYU Sleep Disorders Center. If bedtime is 11 p.m., shift it to 10:45 p.m. The next week, shoot for 10:30 p.m., and so on. Continue until you wake up on your own, refreshed.
Keep in mind that stimulants like caffeine and sugar, taken too close to bedtime, can keep you awake — and hurt your quality of sleep. Alcohol can disrupt sleep. Lights, even the glow from a computer or TV, signal your body to stay awake. Even catching up with your email before you turn in makes it harder to drift off because your body gets into task mode. Instead, try reading, journaling, listening to relaxing music or soaking in a warm bath (“Bookends”). It’s ideal to transition into these activities an hour before bedtime.
Try setting goals for sleep duration, consistency and quality, Freebeck says. Address disruptions to those goals, and if you still don’t feel rested, it might be time to consult a doctor to see if you might have sleep apnea or another undiagnosed sleep disorder.
If it turns out that the biggest barrier to your getting enough sleep is simple lack of time, or if you’re trading off sleep in the interest of “getting more done,” Dement would have you reconsider your choices: “You can sleep for six hours a night and be a zombie for 18 hours,” he says. “Or you can sleep for eight hours a night and be a superman or superwoman for 16 hours a day.”