Not getting adequate sleep won’t just leave you craving a Starbucks fix, it can have a serious negative impact on your health—and may prevent you from losing weight.
Cathryn, a 38-year-old mother of preteen twins, works full-time job at an insurance office, eats healthfully and does Pilates twice a week. But when bedtime comes, she tosses and turns, then frequently awakens at 4 AM., overwhelmed by worries and unable to get back to sleep.
Her boss had warned her she was in danger of losing her job due to careless errors, but it wasn’t until she had a near-miss car accident after she nodded off at the wheel that she realized she had a major problem. “Even though I was dead-tired all the time, it never occurred to me that missing a few hours of sleep was a big deal,” she says. “I figured I could make up the lost hours on the weekend.”
Underestimating the importance of sleep is a common miscalculation. More than 70 million Americans suffer from insufficient sleep, the Centers for Disease Control reports. National Sleep Foundation statistics reveal that only two-thirds of women get a good night’s rest only a few nights per week and that 29 percent regularly take sleeping aids.
“Lack of adequate sleep is a major problem, with an average night’s sleep decreasing from nine hours a night 130 years ago to six and three-quarters hours a night,” says sleep expert Jacob Teitelbaum, MD, medical director of the Fibromyalgia and Fatigue Centers, a nationwide group of clinics.
“Many people don’t prioritize sleep in their lives,” says David Kuhlmann, MD, medical director of Sleep Medicine at Bothwell Regional Health Center in Sedalia, MO. “You have to give yourself enough time to get an adequate amount. People think that the goal of sleep is to sleep. It is not. The goal is to wake up feeling refreshed.”
You can temporarily disguise the effects of sleep loss with concealer or by drinking gallons of coffee to rev you up. But in time, it can also have serious medical consequences such as weight gain, diminished heart health, diabetes, certain cancers, diminished memory and depression. Here, some of the ways your lack of pillow time may be affecting your health:
1. IT CAN CAUSE YOU TO GAIN WEIGHT.
“Insufficient sleep is associated with a 30 percent increased risk of obesity,” says Dr. Teitelbaum.
“Sleep affects metabolism,” explains William Kohler, MD, medical director of the Florida Sleep Institute in Springhill. “When you lose sleep, chemicals in the brain are altered and there are elevated changes in the key appetite hormones, leptin and ghrelin. So lack of sleep can potentially make you eat more, because you won’t have that feeling of being satiated.”
“Sleep loss will trigger fatigue, which causes sugar cravings,” adds Dr. Teitelbaum.
The Nurses Health Study at Case Western Reserve University in Cleveland tracked the sleeping patterns of 68,183 women for 16 years. Those logging in five hours or less gained about 2 ½ pounds more than did those sleeping seven hours.
Even if you’re dieting, evidence suggests that you’ll lose fewer pounds if you’re not getting enough rest. A National Institutes of Health study showed that after two weeks of calorie restriction, the group that got 8 ½ hours of sleep lost about 3 pounds; while the group that got 5 ½ hours lost only about 1.5 pounds.
“Also, over time, sleep loss can cause a significant weight gain resulting fro m decreased energy levels, thus decreased exercise,” Dr. Kohler adds. “You might have the same calorie intake but you’re not as active.”
2. SLEEP DEPRIVATION IS LINKED TO CARDIOVASCULAR DISEASE.
Although many physicians believe that lack of sleep may adversely affect your ticker, most are unwilling to go on the record until clinical studies are 100 percent conclusive. Until then, experts like Dr. Teitelbaum couch it this way: “Poor sleep is associated with an increased risk of metabolic syndrome,” which is the name given to a group of factors that increase the risk for heart disease, stroke, certain cancers and type-2 diabetes among other conditions “Metabolic syndrome is a major risk factor for heart disease in the U.S.,” Dr. Teitelbaum says. “Because of this, insomnia is a predictor of cardiac mortality.”
Studies back up the link. A large 2007 study at the University of Warwick Medical School found that when participants reduced their sleeping hours from seven to five hours or fewer per night, they doubled their risk of death from cardiovascular problems. Seven hours of shut-eye nightly was perceived as an optimal goal.
3. IT CAN INCREASE INFLAMMATION AND DEPRESS YOUR IMMUNE SYSTEM.
When your body gets injured, irritated or infected, inflammation is how it responds. Inflammation has been show to trigger cardiovascular disease, certain cancers, type-2 diabetes and other conditions. A 2010 Emory University study found that people who did not get enough sleep (i.e. got less than six hours a night)—or got poor quality slumber, had higher levels of three inflammatory markers. One in particular, called C-reactive protein (CRP), increased by 25 percent. Chronic elevations of CRP are present in those with heart disease, certain cancers and diabetes.
“Sleep deprivation is a good way to immune-suppress an animal—including people,” says Dr. Teitelbaum. “An optimized immune system is associated with less cancer and infections.
4. LACK OF SLEEP CAN AFFECT YOUR MEMORY.
“Sleep loss results in a decrease in short-term memory,” says Donna Arand, PhD, clinical director of the Kettering Sleep Disorders Center in Dayton, OH. “The greater the loss, the greater the impact on memory. The brain area for memory is smaller in patients who sleep less. My research demonstrates that sleep deprivation impacts memory, fine-motor coordination, mood and cognitive processes.”
Not being well rested also affects the ability to learn new things, process new information and access it after it’s stored. Processing information (called consolidation) takes place during sleep when neural connections are strengthened and memories are formed.
5. CHRONIC INSOMNIA CAN INCREASE YOUR RISK OF DEPRESSION.
Though short-term sleep deprivation “has a remarkably positive effect on depression,” according to Jerome Siegel, PhD, chief of neurobiology research at the VA Greater Los Angeles Healthcare System and a professor of psychiatry at UCLA, “chronic sleep deprivation may precipitate depression.”
Dr. Kohler views the relationship between poor sleep and depression as complex. “The chemicals in the brain that are involved in sleep are also involved in the emotional state. There’s an overlap in transmitters. Most of us feel down the next day with a lack of sleep. Poor sleep can cause difficulty with interpersonal relationships and a decrease of ambition.”
Dr. Teitelbaum sees insomnia and depression as each other’s enablers. “Eighty percent of those with depression have insomnia, and it is suspected that insomnia may increase the risk of depression. In addition, those with insomnia have disrupted patterns with more dreaming and less deep sleep.”
DO YOU HAVE SLEEP APNEA?
If you’re getting enough sleep, but are still exhausted during the day, you may have sleep apnea. If you snore, or have ever woken up gasping for air (or have a partner who’s commented that you struggle to breathe while sleeping), you may suffer from sleep apnea. This can cause you to stop breathing for a few seconds to a minute or two up to 30 times per hour. “In sleep apnea the muscles that normally help to keep the upper airway open collapse together, which may temporarily stop breathing,” Dr. Kuhlmann explains. “The two parts of your body most sensitive to oxygen deprivation are your heart and your brain, which is why sleep apnea has such a strong association with heart problems and strokes.” If you suspect you have this common condition, see your doctor.
Heidi Dvorak is a Los Angeles-based freelance writer who now wears sleep masks to bed. Her work has appeared in Shape, the Los Angeles Times, and Marie Claire.