How Much Sleep Does an Adult Need? Shedding Light on Common Questions About Sleep

Fact checked by Olga Sadouskaya, MD
Clinical Pharmacologist, Chief Medical Officer

How much sleep do you really need?

Most people don’t know the answer to this question. Sleep is one of the most important aspects of our lives, and yet it’s often misunderstood. This article will help shed some light on common questions about sleep so that you can make changes in your life to ensure that you are getting the best sleep possible.

How many sleep stages are there?

There are four different stages of sleep. The initial stage of sleep is non-REM (NREM) sleep, and it consists of three separate stages. The deepest sleep occurs during the last stage of non-REM sleep. This level of sleep is notoriously difficult to get out of.

REM sleep typically occurs 1 to 1.5 hours after you first go to sleep. When you are in REM sleep, you usually have vivid dreams.

NREM stage N1

In most people, the time it takes from being awake to being asleep is confined to this brief, non-REM sleep period. When people are woken from stage N1, the lightest stage of sleep, they often don’t realize they were asleep.

NREM stage N2

The following stage of non-REM sleep is considered a lighter stage of sleep from which you may be quickly woken, and it accounts for the majority of your overall sleep period. Before you go into a deep sleep, you’ll go through this period.

A woman sleeping on her left side with a mask on

NREM stage N3

The deepest level of sleep occurs during the last phase of non-REM sleep. Delta sleep, or N3, is the third stage of sleep. During this last stage of non-REM sleep, your body completes a number of beneficial processes for your health.

REM stage R

There are two different types of REM sleep: phasic and tonic. Phasic REM is characterized by bursts of rapid eye movement, while tonic REM is not. However, both are necessary for a good night’s sleep.

About 90 minutes after falling asleep, you’ll enter stage R, which is commonly referred to as the “dreaming” stage of sleep.

The duration of REM sleep increases by around 10 minutes with each subsequent cycle. Somewhere between 30 and 60 minutes may elapse during stage R’s final cycle.

How much sleep does an adult need?

Adults in good health typically require between 7 and 9 hours of sleep every night. The average amount of sleep shown in experiments to prevent negative effects on daytime function is 8 hours and 10 minutes.

Adults over the age of 65 may require less sleep, on average 7 to 8 hours each night, according to experts’ recommendations.

Spending too much time in bed might lead to restless nights.

The population’s sleep requirements follow a bell-shaped distribution, with most close to the average and outliers on either end.

There is no universally accepted minimum number of hours of sleep, and some people may get along just fine on 6 hours. However, some people may require 9 hours (or more) and experience sleep deprivation if they only get 8 hours.

And how much sleep do kids and teenagers need?

Sleep-deprived children and teenagers are more likely to be overweight and develop diabetes, get injured often, have poor mental health, and have a hard time paying attention and controlling their behavior. But how much sleep does a teenager need?

People of different ages have different sleep requirements. Children aged 6–12 should routinely sleep 9–12 hours every 24 hours, suggests the American Academy of Sleep Medicine, while adolescents aged 13–18 should get 8–10 hours of sleep per day.

What’s the connection between sleep and mental health?

When we sleep, our brains have a chance to refresh and recharge. During deep sleep, our brains analyze and store new information, memories, emotions, and other mental states for later recall.

We may become more forgetful when we don’t get enough sleep since that’s when our brain rests and processes information. So if you forgot your new coworker’s name, you may not have gotten enough rest the night before.

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But that’s not the end of it. During sleep, we also process our feelings. This is why you may be more inclined to get annoyed at the driver who cut you off in traffic after a sleepless night.

Understanding how disturbed sleep affects mental health is difficult. But what is known by scientists is that there is a strong connection between how well you sleep and how well your mind works. After all, our minds and hearts do their deep processing during REM sleep.

Consider that mental rest time like lunchtime or after hours at the workplace. When there are fewer interruptions, you can get more done. The same may be said of the brain. We don’t have to deal with the constant barrage of sensory input when we’re asleep, so our brains are free to process information. If we deprive the mind of this opportunity, we’ll have to pay the price.

Are sleep problems more common in older people?

Generally, seniors are more prone to developing sleep disorders. Although most medical professionals agree that adults need between 7 and 8 hours of sleep nightly, regardless of their age, sleep is less restful and more scattered in the elderly than in younger adults.

The following are common causes of sleep problems in older adults:

  • Alzheimer’s disease
  • Alcohol use
  • Natural body clock shifts that make some people tired earlier in the evening
  • Some prescription drugs, over-the-counter drugs, herbal remedies, and supplements
  • Depression (a prevalent cause of sleep disorders in people of all ages)
  • Problems involving the central nervous system and the brain

What happens to your body when you don’t get enough sleep?

Having bad sleep habits and consistently not getting enough sleep can lead to weight gain, cardiovascular problems, and even diabetes. This happens because our bodies produce hormones involved in regulating hunger, metabolism, and how the body uses glucose while we sleep.

An increase in the production of the stress hormone cortisol has also been linked to inadequate sleep.

Additionally, it appears that sleep deprivation disrupts the balance of other hormones.

Reduced insulin secretion after eating, in combination with elevated cortisol levels, has been linked to an increased risk of developing type 2 diabetes. Moreover, sleep and blood pressure have a close link, so sleep deprivation can also affect your blood pressure.

Is sleep apnea hereditary?

Studies demonstrate that having a close familial relationship with someone with obstructive sleep apnea increases your likelihood of acquiring the condition.

The number of times someone stops breathing during sleep (the Apnea-Hypopnea Index) is estimated to be heritable in roughly 40 percent of cases.

So is sleep apnea a disability? Well, while it is not considered a disability, it can definitely affect the quality of your sleep and your overall well-being.

Unmade bed as a metaphor for how much sleep does an adult need

Can sleep apnea cause weight gain?

Being overweight is a risk factor for developing obstructive sleep apnea. According to the National Heart, Lung, and Blood Institute, a lack of exercise and a poor diet are two major contributors to obesity, which in turn can cause sleep apnea.

In this light, it’s important to consider the effects of gaining weight following a diagnosis of sleep apnea. Sleep apnea’s impact on energy levels is one contributing cause of weight gain.

Can sleep apnea be cured?

Though it’s a valid concern among those who have been diagnosed with sleep apnea, the answer is no. But although sleep apnea is a chronic disorder for which there is currently no cure, it may be managed with medication, lifestyle changes, oral appliances, and surgery.

As we’ve already mentioned, obesity increases the likelihood of developing sleep apnea. So this risk can be mitigated by losing weight. Alternatively, tonsillectomy, nasal surgeries, and nerve stimulation are a few surgical options that can be effective in both children and adults.

But can sleep apnea kill you? Rest assured — there is no need to worry. It is very unlikely to happen.

How to get a good night’s sleep

There are a few things you can do to get a good night’s sleep:

  • Keep your bedroom cool, dark, and quiet. Get rid of all distractions, including TVs, computers, and phones.
  • Establish a regular sleep schedule and stick to it as much as possible. Go to bed and wake up at the same time every day.
  • Avoid caffeine and alcohol before bed. Caffeine can keep you awake for hours, and alcohol can disrupt your sleep patterns.
  • Exercise regularly. Exercise helps promote better sleep quality and duration.
  • Try sleeping on your side. It helps to open the airways and makes breathing easier.


People’s need for sleep varies, but most people require around 8 hours of sleep each night. Although some may feel they can get by on less, research indicates that sleeping fewer than 6 hours per night is linked with compromised health and well-being.

Conversely, sleeping more than 10 hours a day has also been found to be detrimental to health. Too much or too little sleep undermines the body’s ability to function properly.

January 23, 2023