After one night you're...
Hungrier and apt to eat more. Studies have linked short-term sleep deprivation with a propensity to load up on bigger portions, a preference for high-calorie, high-carb foods and a greater likelihood of choosing unhealthy foods while grocery shopping.
More likely to have an accident. Getting six or fewer hours of shut-eye a night triples your risk of drowsy driving-related accidents, according to the National Sleep Foundation's Drowsydriving.org. Plus, just one bad night's sleep can affect a driver's eye-steering coordination, according to research from Manchester Metropolitan University. And sleep deprivation can just make you generally more clumsy, whether you're behind the wheel or not, reports Prevention.
You will not look your best or your most approachable. Beauty sleep is legit. A small study published in the journal SLEEP found that sleep deprived study participants were rated as less attractive and sadder, HuffPost reported at the time. A different study from the Medical Institutet Karolinska in Stockholm, Sweden found that exhausted people are also judged to be less approachable. And the problem only gets worse over time: Researchers have linked chronic sleep deprivation with skin aging.
More likely to get sick. Proper rest is one of the building blocks of a healthy immune system. In fact, one Carnegie Mellon University study found that sleeping fewer than seven hours a night was associated with a tripled risk of coming down with a cold. What's more, the Mayo Clinic explains:
During sleep, your immune system releases proteins called cytokines, some of which help promote sleep. Certain cytokines need to increase when you have an infection or inflammation, or when you're under stress. Sleep deprivation may decrease production of these protective cytokines. In addition, infection-fighting antibodies and cells are reduced during periods when you don't get enough sleep.
Loss of brain tissue. A small, recent study of 15 men, published in the journal SLEEP, found that just one night of sleep deprivation was linked with signs of brain tissue loss, measured by blood levels of two brain molecules that usually increase after brain damage.
More likely to get emotional. One study from researchers at the University of California, Berkeley and Harvard Medical School used functioning Magnetic Resonance Imaging to show that after sleep deprivation, the brain's emotional centers were more than 60 percent more reactive. "It's almost as though, without sleep, the brain had reverted back to more primitive patterns of activity, in that it was unable to put emotional experiences into context and produce controlled, appropriate responses," senior author Matthew Walker, director of UC Berkeley's Sleep and Neuroimaging Laboratory, said in a statement. "Emotionally, you're not on a level playing field."
Less focused and having memory problems. Being exhausted zaps your focus, and can render you more forgetful (no wonder you keep misplacing your cell phone after a bad night between the sheets). On top of that, sleep is thought to be involved in the process of memory consolidation, according to Harvard, which means shortchanging it can make it more difficult to learn and retain new things.
After several nights your...
Stroke risk increases. Research presented at the SLEEP 2012 conference suggested that getting fewer than six hours a night can ratchet up stroke risk for middle- and older-aged people. "These people sleeping less than six hours had a four times increased risk of experiencing these stroke symptoms compared to their normal weight counterparts that were getting seven to eight hours," study researcher Megan Ruiter, of the University of Alabama at Birmingham, told HuffPost at the time.
Obesity risk increases. Not only can short-term sleep loss lead to increased caloric consumption, but multiple studies have suggested a link between chronic sleep deprivation and increased obesity risk over time. One 2012 research review from Penn State, for instance, found that sleeping fewer than six hours a night was linked with changes in levels of the appetite hormones ghrelin and leptin. Another 2012 study published in the American Journal of Human Biology showed that too little sleep was tied to changes in appetite regulation, which could trigger people to eat more. And yet another study from the University of Pennsylvania found that study participants who were sleep deprived for five nights in a row gained about two pounds, perhaps because of late night snacking.
Risk of some cancers may increase. One Cancer study of 1,240 participants who underwent colonoscopies found that those who slept fewer than six hours a night had a 50 percent spike in risk of colorectal adenomas, which can turn malignant over time. Another 2012 study identified a possible link between sleep and aggressive breast cancers. Researchers have also suggested a correlation between sleep apnea and increased cancer risk of any kind.
Diabetes risk increases. A 2013 study from the Centers for Disease Control and Prevention found that too little (and too much!) sleep was linked with a host of chronic diseases, including Type 2 diabetes. And the same 2012 study that found that sleep deprivation was linked to hormonal changes associated with obesity also found that too little sleep was tied to decreased insulin sensitivity, a diabetes risk factor.
Heart disease risk increases. Chronic sleep deprivation has been associated with high blood pressure, atherosclerosis (or cholesterol-clogged arteries), heart failure and heart attack, Harvard Health Publications reports. A 2011 study from Warwick Medical School researchers found that inadequate shut-eye was tied to heart attack risk, as well as cardiovascular disorders and stroke. "If you sleep less than six hours per night and have disturbed sleep you stand a 48 percent greater chance of developing or dying from heart disease and a 15 per cent greater chance of developing or dying of a stroke," lead author Francesco Cappuccio said in a statement on the findings, which were published in the European Heart Journal. "The trend for late nights and early mornings is actually a ticking time bomb for our health so you need to act now to reduce your risk of developing these life-threatening conditions."
Sperm count decreases. Besides the obvious fact that exhaustion isn't typically conducive to getting busy, skipping your Zzs can take a hit on fertility. A 2013 study published in the American Journal of Epidemiology of 953 young men in Denmark found that those with high levels of sleep disturbances had a 29 percent lower concentration of sperm in their semen.
Risk of death increases. A SLEEP study evaluating 1,741 men and women over the course of 10 to 14 years found that men who slept fewer than six hours had a significant increase in mortality risk, even after adjusting for diabetes, hypertension and other factors.
Insufficient Sleep Is a Public Health Epidemic
Sleep is increasingly recognized as important to public health, with sleep insufficiency linked to motor vehicle crashes, industrial disasters, and medical and other occupational errors.1 Unintentionally falling asleep, nodding off while driving, and having difficulty performing daily tasks because of sleepiness all may contribute to these hazardous outcomes. Persons experiencing sleep insufficiency are also more likely to suffer from chronic diseases such as hypertension, diabetes, depression, and obesity, as well as from cancer, increased mortality, and reduced quality of life and productivity.1 Sleep insufficiency may be caused by broad scale societal factors such as round-the-clock access to technology and work schedules, but sleep disorders such as insomnia or obstructive sleep apnea also play an important role.1 An estimated 50-70 million US adults have sleep or wakefulness disorder1. Notably, snoring is a major indicator of obstructive sleep apnea.
In recognition of the importance of sleep to the nation's health, CDC surveillance of sleep-related behaviors has increased in recent years. Additionally, the Institute of Medicine encouraged collaboration between CDC and the National Center on Sleep Disorders Research to support development and expansion of adequate surveillance of the U.S. population's sleep patterns and associated outcomes. Two new reports on the prevalence of unhealthy sleep behaviors and self-reported sleep-related difficulties among U.S. adults provide further evidence that insufficient sleep is an important public health concern.
Sleep-Related Unhealthy Behaviors
The Behavioral Risk Factor Surveillance System (BRFSS) survey included a core question regarding perceived insufficient rest or sleep in 2008 (included since 1995 on the Health Related Quality of Life module) and an optional module of four questions on sleep behavior in 2009. Data from the 2009 BRFSS Sleep module were used to assess the prevalence of unhealthy/sleep behaviors by selected sociodemographic factors and geographic variations in 12 states. The analysis, determined that, among 74,571 adult respondents in 12 states, 35.3% reported <7 hours of sleep during a typical 24-hour period, 48.0% reported snoring, 37.9% reported unintentionally falling asleep during the day at least once in the preceding month, and 4.7% reported nodding off or falling asleep while driving at least once in the preceding month. This is the first CDC surveillance report to include estimates of drowsy driving and unintentionally falling asleep during the day. The National Department of Transportation estimates drowsy driving to be responsible for 1,550 fatalities and 40,000 nonfatal injuries annually in the United States.2
Self-reported Sleep-related Difficulties among Adults
The National Health and Nutrition Examination Survey (NHANES) introduced the Sleep Disorders Questionnaire in 2005 for participants 16 years of age and older. This analysis was conducted using data from the last two survey cycles (2005–2006 and 2007–2008) to include 10,896 respondents aged ≥20 years. A short sleep duration was found to be more common among adults ages 20–39 years (37.0%) or 40–59 years (40.3%) than among adults aged ≥60 years (32.0%), and among non-Hispanic blacks (53.0%) compared to non-Hispanic whites (34.5%), Mexican-Americans (35.2%), or those of other race/ethnicity (41.7%). Adults who reported sleeping less than the recommended 7–9 hours per night were more likely to have difficulty performing many daily tasks.
How Much Sleep Do We Need? And How Much Sleep Are We Getting?
How much sleep we need varies between individuals but generally changes as we age. The National Institutes of Health suggests that school-age children need at least 10 hours of sleep daily, teens need 9-105 hours, and adults need 7-8 hours. According to data from the National Health Interview Survey, nearly 30% of adults reported an average of ≤6 hours of sleep per day in 2005-2007.3 In 2009, only 31% of high school students reported getting at least 8 hours of sleep on an average school night.4
Sleep Hygiene Tips
The promotion of good sleep habits
and regular sleep is known as sleep hygiene. The following sleep
hygiene tips can be used to improve sleep.
- Go to bed at the same time each
night and rise at the same time each morning.
- Avoid large meals before bedtime.
- Avoid caffeine and alcohol close to
- Avoid nicotine.
- (Sleep Hygiene Tips adapted from
the National Sleep Foundation)
1. Institute of Medicine. Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. Washington, DC: The National Academies Press; 2006.
2. US Department of Transportation, National Highway Traffic Safety Administration, National Center on Sleep Disorders Research, National Heart Lung and Blood Institute. Drowsy driving and automobile crashes [National Highway Traffic Safety Administration Web Site]. Available athttp://www.nhtsa.gov/people/injury/drowsy_driving1/Drowsy.html#NCSDR/NHTSAAccessed February 10, 2011.
3. Schoenborn CA, Adams PF. Health behaviors of adults: United States, 2005–2007. National Center for Health Statistics. Vital Health Stat 10(245). 2010.
4. CDC. Youth Risk Behavior Surveillance—United States, 2009. MMWR 2010;59:SS-5.