Why is sleep so important? Missing even 90 minutes of sleep for just 1 night can reduce your daytime alertness by as much as 32%. That’s enough to impair your memory, your thinking ability, and your safety on the job and on the road. One Australian study found that volunteers who stayed awake 6 hours past their normal bedtime for a single day performed as poorly on tests gauging attentiveness and reaction time as those who were legally drunk. The National Sleep Foundation’s 2009 poll showed that as many as 1.9 million drivers have had a car crash or a near miss due to drowsiness in the past year. Here are a few more reasons snoozing is important for your health:
It maintains a strong immune system. Sleep deprivation compromises immune function and makes you more vulnerable to disease.It slows aging. Too little sleep elevates levels of stress hormones and lowers levels of growth hormone, necessary for cell repair. In one study, young, healthy sleep-deprived subjects had the hormonal profiles of much older people.It prevents diabetes. Sleeplessness increases insulin resistance, a precursor to type 2 diabetes.It keeps you slim. When you’re sleep deprived, you have more of the appetite-stimulating hormone ghrelin in your blood and less appetite-curbing leptin, a combo that leaves you longing for junk food.It can make you happier. Insomniacs face a higher risk of depression, alcoholism, and suicide.
How can I tell if I’m sleep deprived? Our bodies give us plenty of signals when we’re tired. But some of us are so used to being sleep deprived that we remain oblivious to how impaired we really are. Sleep debt isn’t something you can pay off in a weekend, researchers say—it can take weeks of building up restorative sleep habits. Here are some signs you may need to make sleep a more urgent priority.
You’re still hungry even after eating all day. Studies show that chronic sleep loss can disrupt blood sugar levels and cause the body to produce less leptin, a hormone that curbs appetite, and more ghrelin, leptin’s hunger-stimulating counterpart. Because of these physiological changes, you may be more likely to overeat when you skimp on sleep.You keep getting sick. Inadequate sleep can leave you more vulnerable to infection than those who are well rested.You cry easily. When we’re sleep deprived, we may also feel glum because tired brains store negative memories more effectively than positive or neutral ones.You act like a klutz. Sleepy people may be clumsier for several reasons: Impaired reflexes and a lack of focus may make it hard for them to react quickly enough to things that spring up in their path.
Aren’t there just some people who don’t need a lot of sleep? If you genuinely require less than 6 hours of sleep a night, you’re a rarity. A just-discovered genetic mutation does enable some people to function okay on 20 to 25% less sleep than average, but—here’s the catch—researchers estimate that fewer than 1% of people have the trait. Two likely signs you’re among the lucky short-sleeping crowd: You wake up regularly without an alarm clock, and at the same time every day—weekdays, weekends, vacations—says Emory University sleep expert David Schulman, MD. “But most of us need 7 to 8 hours of sleep to stay healthy.” Why can’t I fall asleep? There could be a number of lifestyle habits or other factors stealing your slumber. They may include: Y ou oversleep on weekends. Late nights followed by extra sack time the next morning throw off your internal clock, which is controlled by a cluster of nerve cells in the brain that also regulate appetite and body temperature, says Lawrence Epstein, MD, medical director of Sleep Health Centers in Brighton, MA, and author of The Harvard Medical School Guide to a Good Night’s Sleep. When Sunday rolls around, you’re reprogrammed to stay up past your bedtime, and you feel like a zombie on Monday morning. Hormonal changes. Fluctuating levels of estrogen and progesterone before or during your period or throughout perimenopause can sabotage sleep, says Joyce Walsleben, PhD, an associate professor of medicine at NYU School of Medicine. You may notice problems–mainly waking up during the night–long before you start having hot flashes, she says. You sleep tight with dust mites. You could be sharing your bed with anywhere from 100,000 to 10 million dust mites, says Alan Goldsobel, MD, a fellow of the American Academy of Allergy, Asthma & Immunology in San Jose, CA, and the residue they leave behind can trigger mild to very severe allergies. Your bedroom is a mess. You keep a messy pile of papers on your nightstand…and your desk…and the floor. A cluttered sleep environment makes for a cluttered mind–the kind that churns well into the night. Stress is the number one cause of short-term sleep problems such as frequent middle-of-the-night waking and insomnia, according to the American Psychological Association. What is insomnia? We all experience an occasional toss-and-turn night, but insomnia–the inability to fall or stay asleep, or waking up and still feeling tired–can become frustrating if it occurs often. About 30 to 40% of adults have insomnia on occasion; about 10 to 15% struggle with chronic bouts, according to the National Sleep Foundation. If you feel tired all the time, don’t blow it off. Give yourself about 2 to 3 weeks to make some lifestyle changes. Get more sleep, trim your social calendar, eat more wholesome foods, drink more fluids, take a multivitamin, and cut back on caffeine and alcohol. “If you’re still feeling the symptoms of fatigue after those changes, then you need professional help,” says Sandra Adamson Fryhofer, MD, an internal medicine doctor in Atlanta. Excess exhaustion could be the sign of a more serious medical condition that can be treated, such as depression or a thyroid disease. Do naps help, or hurt? Some people swear that quick naps make them sleepier, but a snooze that’s less than 20 minutes should perk most of us up. “Just 10 to 20 minutes is all you need to get the benefits of napping, such as alertness, improved performance, and better mood,” says Kimberly A. Cote, PhD, a sleep researcher at Brock University in Ontario. Here’s why: During sleep, your brain produces different kinds of waves, which correspond to how deeply you sleep. After about 20 minutes, the sleeping brain may move into what’s called slow-wave sleep, which is the deepest phase of sleep. If you nap too long, you may feel groggy and disoriented upon awakening instead of refreshed because long naps are more likely to contain deep slow-wave sleep. When you nap also matters. “A power nap should be early in the day so it doesn’t interfere with your ability to fall asleep at bedtime,” says David Neubauer, MD, associate director of the Johns Hopkins Sleep Disorders Center. Most people’s inner body clocks trigger drowsiness somewhere between 1 and 3 PM. Will working out keep me up at night? Exercise too close to bedtime may affect how well you sleep. However, it varies by person. Research shows that even vigorous exercise right before bedtime doesn’t cause trouble sleeping for many people (and in some cases it may help). This is good news if your busy schedule gives you a short window of time after work to squeeze in some activity. Even people who have trouble sleeping can probably exercise about an hour before bed without problems. “But we don’t have hard data, so people really have to do their own testing,” says Michael Perlis, PhD, director of the University of Pennsylvania Behavioral Sleep Medicine Program. Experiment. If you exercise at night and suspect that your workout may be keeping you up, reschedule it for earlier in the day for several days to see whether you sleep better. Keeping a sleep diary for those days—noting when you exercise and how well you sleep—can help. If you find you do sleep better when you exercise earlier, make the switch permanent. Could my diet affect my sleep? Digesting food takes energy, so if you have a heavy meal late in the day, your body will work hard digesting it while you’re trying to sleep. Aim to have balanced meals instead and to make breakfast your biggest meal of the day. Also steer clear of greasy eats. A late-night pizza slice can trigger heartburn—that burning sensation in your esophagus—and derail slumber. If you’re prone to indigestion, avoid fatty or citrus foods (as well as chocolate, spicy foods and carbonated beverages) close to bedtime. The food flavor MSG could also trigger insomnia, so check food labels for the ingredient. Coffee is the most obviously sleep stealer, but other sneaky sources of caffeine includes chocolate and certain medications. How can I get a better night’s sleep? Try developing a sleep ritual to get your body and mind prepped for bed: Experts advise us to find relaxing activities in the evening to prepare us for slumber. “It should be something you do every night to signal to the body that it’s time to unwind,” explains clinical psychologist Michael Breus, PhD, fellow of The American Academy of Sleep Medicine. Breus recommends a “Power Down Hour”: 20 minutes of doing things you have to finish, 20 minutes for personal hygiene, and 20 minutes for “relaxation”—however you define it. Also, keep your room cool but your feet warm. Most sleep researchers advise keeping your bedroom cool, but not cold—the National Sleep Foundation recommends between 54 and 75°F. This is because a cool room makes it easier for your core body temperature to drop, which must occur for you to fall asleep. (Body temp reaches its lowest point about 4 hours after you nod off.) However, the thermostat is only part of the story: Proper air circulation and blankets that aren’t too heavy—a big problem in hotel rooms—can also facilitate a drop in body temperature. A series of fascinating studies done in the past decade and a half by Swiss researchers Kurt Kräuchi and Anna Wirz-Justice, PhD, found an inverse relation between warm feet and cool body temp: When your feet and hands are warm, the blood vessels dilate, allowing heat to escape and body temperature to fall, initiating sleep. Conversely, when hands and feet are cold, the vessels constrict, retaining heat—which may keep you awake. So try wearing socks to bed rather than piling on extra blankets. What natural remedies can help me sleep soundly? Sleep supplements have a long history of helping people get the Zzzs they urgently need (too-little sleep is linked to a host of other serious concerns, including high blood pressure, weight gain, and diabetes). Here, the top ones to discuss with your doctor: Melatonin: This hormone, sometimes in short supply in people with insomnia, helps regulate your sleep-wake cycle. Your brain’s pineal gland churns it out naturally at nighttime and halts production in response to morning light, which energizes your body for the day ahead. Acting as the body’s sandman, melatonin slows body functions and lowers blood pressure; this causes a dip in core body temperature and helps trigger sleep. Many experts recommend melatonin for specific sleep issues, like jet lag. Valerian: For thousands of years, herbalists have relied on the woody roots of valerian to calm the anxious and relax the sleepless. Though studies on its efficacy are mixed, valerian is one of the most popular alternative remedies for sleep issues. One of the herb’s biggest perks: It may improve your quality of sleep without leaving you feeling groggy the next morning, as many prescription sleeping pills can. How do I stay energized during the day? To beat an afternoon slump, take a walk outdoors. Just as it does in the early morning, light later in the day may blunt an afternoon energy dip, which often comes on like clockwork. “Because of the way the homeostatic and circadian systems interact, most people feel a lull 17 to 18 hours after they went to bed the previous night,” says Marianna Figueiro, PhD, program director of Rensselaer Polytechnic Institute’s Lighting Research Center. Step outside into revitalizing sunlight for a short walk. Vary your routine by taking a different path every day, doing a short errand, or catching up with a friend on your cell phone. If you can’t get outside, plant yourself next to a window, open the shades wide, and look out. Also try giving yourself a face rub. “Massaging your face boosts circulation, making it a surefire way to wake up,” says Maggy Dunphy, spa and wellness director at Stowe Mountain Lodge in Vermont. Starting at your forehead and working down to your chin, lightly flutter tap or drum your fingertips, varying the velocity, intensity, and location until you’ve touched your entire face. Bonus: These moves give you a quick healthy glow. Where can I go to find out more? National Sleep Foundation American Sleep Association
