How much sleep do you need to function properly
But how much sleep do we really need? Until about 15 years ago, one common theory was that if you slept at least four or five hours a night, your cognitive performance remained intact; your body simply adapted to less sleep. But that idea was based on studies in which researchers sent sleepy subjects home during the day — where they may have sneaked in naps and downed coffee. Enter David Dinges, the head of the Sleep and Chronobiology Laboratory at the Hospital at University of Pennsylvania, who has the distinction of depriving more people of sleep than perhaps anyone in the world. In what was the longest sleep-restriction study of its kind, Dinges and his lead author, Hans Van Dongen, assigned dozens of subjects to three different groups for their study: some slept four hours, others six hours and others, for the lucky control group, eight hours — for two weeks in the lab. During the P.SEE VIDEO BY TOPIC: How Much Sleep is Enough?
SEE VIDEO BY TOPIC: Impact of Sleep on Health Video -- Brigham and Women's HospitalContent:
Get Enough Sleep
But how much sleep do we really need? Until about 15 years ago, one common theory was that if you slept at least four or five hours a night, your cognitive performance remained intact; your body simply adapted to less sleep. But that idea was based on studies in which researchers sent sleepy subjects home during the day — where they may have sneaked in naps and downed coffee. Enter David Dinges, the head of the Sleep and Chronobiology Laboratory at the Hospital at University of Pennsylvania, who has the distinction of depriving more people of sleep than perhaps anyone in the world.
In what was the longest sleep-restriction study of its kind, Dinges and his lead author, Hans Van Dongen, assigned dozens of subjects to three different groups for their study: some slept four hours, others six hours and others, for the lucky control group, eight hours — for two weeks in the lab.
During the P. Even a half-second response delay suggests a lapse into sleepiness, known as a microsleep. The P. It measures the sustained attention that is vital for pilots, truck drivers, astronauts. Attention is also key for focusing during long meetings; for reading a paragraph just once, instead of five times; for driving a car. It takes the equivalent of only a two-second lapse for a driver to veer into oncoming traffic.
Not surprisingly, those who had eight hours of sleep hardly had any attention lapses and no cognitive declines over the 14 days of the study. What was interesting was that those in the four- and six-hour groups had P. Though the four-hour subjects performed far worse, the six-hour group also consistently fell off-task. By the sixth day, 25 percent of the six-hour group was falling asleep at the computer. And at the end of the study, they were lapsing fives times as much as they did the first day.
The six-hour subjects fared no better — steadily declining over the two weeks — on a test of working memory in which they had to remember numbers and symbols and substitute one for the other. The same was true for an addition-subtraction task that measures speed and accuracy. All told, by the end of two weeks, the six-hour sleepers were as impaired as those who, in another Dinges study, had been sleep-deprived for 24 hours straight — the cognitive equivalent of being legally drunk. So, for most of us, eight hours of sleep is excellent and six hours is no good, but what about if we split the difference?
What is the threshold below which cognitive function begins to flag? He purposely restricted his subjects to odd numbers of sleep hours — three, five, seven and nine hours — so that together the studies would offer a fuller picture of sleep-restriction. But in the seven-hour group, their response time on the P. Americans average 6. Which means that, whether we like it or not, we are not thinking as clearly as we could be.
They can do the job for only so long, however. But you do in five to seven days. Dinges is now running a long-term sleep restriction and recovery study to see how many nights we need to erase our sleep debt. Not every sleeper is the same, of course: Dinges has found that some people who need eight hours will immediately feel the wallop of one four-hour night, while other eight-hour sleepers can handle several four-hour nights before their performance deteriorates. But deteriorate it will.
There is a small portion of the population — he estimates it at around 5 percent or even less — who, for what researchers think may be genetic reasons, can maintain their performance with five or fewer hours of sleep. There is also a small percentage who require 9 or 10 hours. But they insisted they had adjusted to their new state.
Even 14 days into the study, they said sleepiness was not affecting them. In fact, their performance had tanked. In other words, the sleep-deprived among us are lousy judges of our own sleep needs. We are not nearly as sharp as we think we are. Home Page World U.
Headlines nowadays are filled with information about sleep deprivation killing everything from your productivity to your moods, and with that, the notion of sleep being for the weak has fallen out of vogue. But how much—and how well—do you need to sleep to feel rested, recharged, and ready to tackle all of the challenges an entrepreneur faces in everyday life? Similar to the notion that you need eight glasses of water a day an idea that has been repeatedly debunked , there is the idea that you need eight uninterrupted hours of sleep per night.
Sleep is an important part of your daily routine—you spend about one-third of your time doing it. Quality sleep — and getting enough of it at the right times -- is as essential to survival as food and water. Sleep is important to a number of brain functions, including how nerve cells neurons communicate with each other. In fact, your brain and body stay remarkably active while you sleep. Recent findings suggest that sleep plays a housekeeping role that removes toxins in your brain that build up while you are awake.
How Much Sleep Do You Really Need?
Most adults need 7 to 8 hours of good quality sleep on a regular schedule each night. Make changes to your routine if you can't find enough time to sleep. This helps you naturally get sleepy at night and stay alert during the day. If you have to work at night and sleep during the day, you may have trouble getting enough sleep. It can also be hard to sleep when you travel to a different time zone. If you are having trouble sleeping, try making changes to your routine to get the sleep you need. Sleep disorders can cause many different problems. People with sleep disorders generally experience these problems on a regular basis. If you have any of these signs, talk to a doctor or nurse.
How much sleep do we really need?
When you think of what makes up a healthy lifestyle, diet and exercise come to mind, but did getting enough restful sleep? Some researchers consider the lack of sleep that many people get to be at epidemic levels. According to the National Institutes of Health , lack of restful sleep causes a long list of issues:. They're listed as ranges because gender has an influence, as well as lifestyle and health. Newborns don't have an established c ircadian rhythm ; it isn't established they're months old.
How much sleep do we really need, and what happens if we get too little or too much? We spend about a third of our lives sleeping, so you've asked an important question. The National Sleep Foundation recommends seven to eight hours of sleep for people over age 64 and seven to nine hours for ages 18 to Kids need more sleep.
How much sleep do you really need?
Sleep is a vital indicator of overall health and well-being. Sleep needs vary across ages and are especially impacted by lifestyle and health. The National Sleep Foundation released the results of a world-class study that took more than two years of research to complete — an update to our most-cited guidelines on how much sleep you really need at each age.SEE VIDEO BY TOPIC: How Much Sleep Do You Actually Need?
It is well known that as children get older they need less sleep. Different people have different sleep needs. The advice in the table below is only a guide. You can make a good guess if a person is sleeping enough at night - observe how they act and function during the day. The above sleep duration recommendations are based on a report of an expert panel convened by the US based National Sleep Foundation and published in in their journal Sleep Health.
The rule that everyone needs eight hours of sleep is a myth
The quality of your sleep directly affects your mental and physical health and the quality of your waking life, including your productivity, emotional balance, brain and heart health, immune system, creativity, vitality, and even your weight. No other activity delivers so many benefits with so little effort! But even minimal sleep loss can take a substantial toll on your mood, energy, mental sharpness, and ability to handle stress. And over the long-term, chronic sleep loss can wreak havoc on your mental and physical health. While you rest, your brain stays busy, overseeing biological maintenance that keeps your body running in top condition, preparing you for the day ahead. By addressing any sleep problems and making time to get the sleep you need each night, your energy, efficiency, and overall health will go up. Fact: You may not be noticeably sleepy during the day, but losing even one hour of sleep can affect your ability to think properly and respond quickly.
Sleep deficiency is a broader concept. It occurs if you have one or more of the following:. Sleeping is a basic human need, like eating, drinking, and breathing. Like these other needs, sleeping is a vital part of the foundation for good health and well-being throughout your lifetime.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Sleep disorders expert Harneet Walia, MD , says sleep is crucial for our health — and many of us are lacking when it comes to it.
Many of us try to live by the mantra eight hours of work, eight hours of leisure, eight hours of rest. Conventional wisdom has long told us we need eight hours of sleep per day, but some swear they need more, and some politicians, mostly say they function fine on four or five. So is the human brain wired to require eight hours, or is it different for everyone? We asked five experts if everyone needs eight hours of sleep per day.
You might start to plan a coping strategy — maybe three pumps of espresso and an ice cold shower to boot. The U. Department of Health and Human Services recommends the average adult clock in seven to eight hours of sleep per night, but for some people, less is apparently more. Seriously, who runs the world?