How much sleep do u need to function
The amount of sleep that a healthy individual needs is largely determined by two factors: genetics and age. Genetics plays a role in both the amount of sleep a person needs, as well as his or her preference for waking up early these are the so-called "larks," or morning-type individuals or staying up late these are the "owls," or evening-type people. Although our internal clock is set to approximately 24 hours, if your clock runs faster than 24 hours, you tend to be a "lark" and wake up early; if your clock runs more slowly, you tend to be an "owl" and go to bed later. The majority of healthy adults require between 7. This is true from young adulthood through late in life, though many older people have difficulty sleeping in a single block of time each night. Generally, sleep needs during a hour period follow this pattern:.SEE VIDEO BY TOPIC: Real Questions - Is getting too much sleep bad for you?
SEE VIDEO BY TOPIC: How Much Sleep is Enough?Content:
The rule that everyone needs eight hours of sleep is a myth
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.
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How Much Sleep Do You Really Need Each Night?
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.
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.
How Little Sleep Can You Get Away With?
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. The panelists participated in a rigorous scientific process that included reviewing over current scientific publications and voting on how much sleep is appropriate throughout the lifespan. The recommendations now define times as either a recommended; b may be appropriate for some individuals; or c not recommended. The panel revised the recommended sleep ranges for all six children and teen age groups. A summary of the new recommendations includes:. To begin a new path towards healthier sleep and a healthier lifestyle, begin by assessing your own individual needs and habits. See how you respond to different amounts of sleep. To pave the way for better sleep, follow these simple yet effective healthy sleep tips, including:.
Assess Your Sleep Needs
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.
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?
Most adults need at least seven or more hours of sleep each night. The National Sleep Foundation NSF and a panel of 18 experts combed through more than studies to identify the ideal amount of time a person needs to sleep according to their age:. Although most men and women need about 7 to 8 hours of sleep per night, their sleep patterns are generally different.SEE VIDEO BY TOPIC: What Happens To Your Body And Brain If You Don't Get Sleep - The Human Body
How much sleep do we really need?
How Much Sleep Do You Really Need?
How Many Hours of Sleep Do You Really Need?