Is 5 Hours Of Sleep Enough? Sleep Doctors Explain

Sleep is essential for good physical and mental health, but many Americans don’t get enough of it. Even if we know we need more rest, the demands of modern life often get in the way. Between work, school, parenting or late night doom-scrolling, it’s easy for sleep to get cut short.

One-third of adults in the United States report that they usually get less than the recommended amount of sleep, which is seven or more hours, according to the U.S. Centers for Disease Control.

If you regularly sleep five hours a night, you may be wondering about the health consequences. What happens if you only sleep five hours a night? Is five hours of sleep at night enough? What are the long-term effects? We spoke to a few sleep experts to find out.

Is 5 hours of sleep enough?

No, five hours of sleep in a 24-hour period is not enough for the vast majority of adults, according to experts. “Five hours is just too little sleep, especially if you’re doing it routinely,” Shelby Harris, Psy.D., clinical psychologist specializing in behavioral sleep medicine and director of sleep health at Sleepopolis, tells TODAY.com.

When it comes to sleep needs, there is no magic number. Age, genetics and underlying health all play a role. However, if you look at the sleep needs of the adult population, the distribution is shaped like a bell curve, with the majority of people falling in between seven to nine hours.

“If you have no external pressures and could go to sleep once you feel drowsy, sleep the amount of time the body needs, then wake up without having to use an alarm, feeling rested … that is how much you need,” Dr. Bhanu Kolla, a sleep physician and psychiatrist at the Mayo Clinic, tells TODAY.com.

In this situation, most healthy people will naturally sleep seven to nine hours, says Kolla. This is why experts and the American Academy of Sleep Medicine recommend adults sleep seven or more hours per night on a regular basis to promote optimal health.

However, some people may need slightly more or less than this amount every night. Some adults may not feel rested unless they sleep nine or 10 hours, and that’s OK, Kolla notes. Other people can function on closer to five hours, but sleeping this amount regularly is not optimal for health, according to experts.

RELATED: Is 6 hours of sleep enough?

There are natural “short-sleepers,” who can sleep less than six hours a night and function normally without feeling tired or facing adverse health outcomes, Dr. Andrew Varga, a neuroscientist and physician at the Mount Sinai Integrative Sleep Center, tells TODAY.com. However, this is due to a rare inherited gene mutation, Varga adds. Natural short-sleepers only make up a tiny subset of the population.

Although many people convince themselves they are short-sleepers, says Harris, sleeping an average of five hours a night is more often due to external factors, stress, poor sleep hygiene or sleep disorders.

Just because you can get away with sleeping only five hours doesn’t mean you should, the experts note.

We all have a rough night of sleep from time to time, but it’s important to be aware that not getting enough quality sleep has short- and long-term health consequences.

Health impact of only sleeping 5 hours a night

After sleeping five hours in one night, most people can catch up with one or two nights of sleeping their normal amount or a few hours extra, says Kolla. A brief nap the next day can also help.

People who consistently sleep less than seven hours a night may “adapt” in a sense, and not feel as sleepy over time as the body racks up sleep debt, Kolla explains. However, getting used to not sleeping enough doesn’t stop the harmful health effects from adding up.

When sleeping too little becomes a pattern and you don’t catch up, this can lead to chronic sleep deprivation, which is associated with a host of long-term health effects, the experts note.

Cognitive functioning

In the short-term, not sleeping enough can negatively impact cognitive functioning the next day. “Even with one night of very little sleep in comparison to what your baseline might normally be, we see issues with impairment,” says Harris.

In addition to feeling sleepy, you may have difficulty concentrating, remembering things, a slower reaction time, and you might be more irritable than usual, the experts note. You may notice it negatively affects performance at work or school.

Accidents and falls

Sleep deprivation can also increase a person’s likelihood of getting into serious accidents.

Losing too much sleep can impair one’s functioning similar to a blood alcohol content of .08% (legally drunk), Harris explains. The less sleep, the greater risk of falls or car crashes, for example.

Heart and kidney problems

In the long term, people who habitually sleep less than six hours have a higher incidence of high blood pressure and heart attacks, says Varga, as well as stroke, heart disease, kidney disease and diabetes, the experts note.

Depression and other mental issues

Research has shown that sleep deprivation is associated with an increased risk of psychiatric illnesses, says Kolla, including depression, anxiety, bipolar disorder, as well as neurological diseases, like Alzheimer’s.

The National Sleep Foundation’s 2023 Sleep in America Poll, which surveys a nationally representative sample of the U.S. population, found that 65% of adults who are dissatisfied with their sleep experience mild or greater levels of depressive symptoms.

“Over what length of time these health consequences start to kick in, it’s hard to tell, but we know the longer you go getting very little sleep, the greater risk,” says Kolla.

What’s the recommended amount of sleep?

Individuals have different sleep requirements during different stages of life, says Kolla. Infants and young children need much more sleep than adults and older adults. Among individuals of the same age group, sleep needs are influenced by medical, environmental, behavioral factors, per the ASSM.

How much sleep you need will can also vary slightly depending on your lifestyle and activity level during the day.

The recommended sleep needs for each age group (per 24 hours), according to the American Academy of Sleep Medicine and CDC, is:

• Infants (4–12 months): 12–16 hours, including naps
• Toddlers (1–2 years): 11–14 hours, including naps
• Young children (3–5 years): 10–13 hours, including naps
• School-age children (6–12 years): 9–12 hours
• Teenagers (13–18 years): 8–10 hours
• Adults (18+ years): 7 or more hours

Generally, you know you got enough sleep “if you awaken feeling refreshed and you’re able to function throughout your day at a normal level without overwhelming sleep drive or the need to take naps” Varga says.

Quality of sleep

Sleep quality matters in addition to duration, the experts note. People should be progressing through the various sleep stages, including non-REM and REM sleep, for the appropriate amount of time. This is referred to as your “sleep architecture,” Varga adds.

A disrupted sleep architecture can impact sleep quality and also lead to sleep deprivation. One of the most common disruptions is sleep apnea, which causes breathing abnormalities through the night, says Kolla. Sleep disorders such as insomnia and environmental factors can also disrupt sleep architecture.

“If people are getting a sufficient amount of hours of sleep (but) waking up not feeling rested or still feel sleepy through the day, that may be an indication that the quality is poor,” says Kolla.

It’s also important to be as consistent as possible with the amount of time you’re sleeping and the timing, the experts note.

How to get more sleep

The first step to getting more sleep is treating sleep like a priority, says Harris. It’s easier said than done. Here are some tips to try.

Limit time on devices

Spending time on our devices, scrolling through social media or watching videos often takes priority instead and keeps people awake, Kolla notes.

“Screens emit blue light, which is a wavelength that hits neurons … involved in regulating sleep and wakefulness,” says Varga, adding that this can delay your circadian rhythm so you may feel sleepy or fall asleep later than normal. While this isn’t a problem for everyone, says Varga, he does recommend avoiding screens for 30 minutes to an hour before bedtime.

It’s just as important to set limits and impose wind-down routines for children as it is for adults, Harris emphasizes. “I think people need to parent ourselves, essentially,” she adds.

Limit substance use

Substances can also influence sleep, says Kolla, namely caffeine and alcohol. These can delay or disrupt sleep, especially when consumed excessively or too close to bedtime, Kolla adds.

Exercise

Exercising regularly can help promote healthy sleeping habits, the experts note, as well as a balanced, nutritious diet.

If you’re concerned about your sleep habits or they are impacting your daily life, talk to your doctor, the experts note. “There’s a big difference between having insomnia or sleep apnea versus people who are just not making sleep a priority,” says Harris.