How Much Sleep Do You Need For Your Age?
Our sleep needs change as we age. The number of hours required varies greatly from the time we are babies to our senior years.
With the demands of modern life greater than ever, the number of adults getting the recommended hours of sleep has decreased — Surveys show that 30% of adults aged 30-64 getting six hours or less in 2004 compared to only 2% of a sample surveyed in 1960.
We're all about promoting healthy sleep here at OptimumSleep, which is why we've produced this guide that answers the question of how many hours of sleep you need for your age.
It also covers the signs you may not be getting enough sleep and how a lack of sleep may affect your health and everyday life.
How Many Hours of Sleep Do You Need?
The expert consensus from The National Sleep Foundation, The American Academy of Sleep Medicine, and the Sleep Research Society is that adults aged 18-65 require 7-9 hours of sleep, and seniors aged 65+ require 7-8 hours.
The range of sleep hours required for children is much larger, with newborns needing 14-17 hours. Sleep requirements drop throughout childhood, with 8-10 hours recommended for teenagers.
The recommendations in the table below are from The National Sleep Foundation-convened expert panel who evaluated scientific literature on the subject, and consensus recommendations by the American Academy of Sleep Medicine (AASM) and the Sleep Research Society (SRS).
|Age Range||Recommended Sleep Duration|
|Newborn (0-3 months)||14-17 hours|
|Infants (4-12 months)||12-16 hours|
|Toddlers (1-2 years)||11-14 hours|
|Preschoolers (3-5 years)||10-13 hours|
|School Age (6-12 years)||9-12 hours|
|Teenagers (13-18 years)||8-10 hours|
|Adults (18-65 years)||7-9 hours|
|Adults (65+)||7-8 hours|
Is Getting Six Hours of Sleep Enough?
While many adults consistently operate on only six or seven hours of sleep each night, the recommended number of hours for optimal sleep is 7-9 hours once we reach adulthood.
A mutation has been discovered in the gene DEC2 (that controls levels of a hormone that helps regulate wakefulness called orexin) that allows people with it to function normally on only four to six hours of sleep each night.
Unfortunately for most of us, this gene mutation is rare, meaning unless you are getting the recommended seven to nine hours, it’s likely you’re not getting enough sleep.
Why Do Babies and Children Need More Sleep Than Adults?
There’s a stark difference between the number of hours of sleep required by babies and children and the number of hours needed by adults.
This difference is down to the physical and mental development of babies and young children.
From the moment a baby is born, it undergoes constant and rapid change, growing both physically and cognitively.
Studies show a positive correlation between infant sleep and memory, language, executive function, and overall cognitive development.
The Way We Sleep Changes as We Age
As we age, there are significant changes to our sleep architecture — the way our sleep is structured in terms of the different stages that make up our overall sleep cycle.
How Our Sleep Cycles Change With Age
Babies and young children have a much shorter sleep cycle than adults:
- Newborns have a sleep cycle that lasts approximately 40 minutes.
- In infants, this increases to 50 minutes.
- Toddlers and very young children have a sleep cycle that lasts approximately 60 minutes.
- The adult sleep cycle lasts anywhere between 90-120 minutes, and this milestone is usually reached by age five.
What About REM Sleep? Does This Change With Age Too?
Yes — due to the significant mental and cognitive development babies and young children undergo, they have a greater REM sleep requirement.
While the exact functions of REM sleep are not decisively known, it is thought to play a role in memory consolidation; babies have a greater need for this due to the sheer amount of new experiences, environments, and people they are exposed to.
Babies and young children spend more time in both deep NREM-3 sleep (the restorative, rejuvenating sleep that allows us to wake feeling refreshed) and REM sleep than adults. In fact, babies spend twice as long in REM sleep than adults.
Circadian Rhythm Development
As anybody with children knows, babies do not sleep in a long block once a day like us adults do — which is precisely why parents’ sleep suffers!
The sleep of newborns is sporadic, and they will cycle through periods of sleep and feeding (and the not-so-fun stuff like pooping and crying) over a 24-hour period.
This sporadic sleep is because they have not gone through the process of entrainment that syncs the circadian rhythm with the light-dark cycle.
The circadian rhythm does not become fully entrained in babies until about 3-4 months of age, which is why the sleep-wake cycle spans much of the day, and long periods of undisturbed sleep are uncommon.
The need for naps throughout the day diminishes as children get older and will typically stop entirely between the ages of five and seven when sleep patterns will mirror that of adults, with one undisturbed block of sleep at night (hallelujah!).
What Happens to Our Sleep as We Age?
Once we reach our late teens, our sleep requirements will stay the same for the bulk of our adult life, but despite the need for sleep remaining the same, we generally sleep less, and there are noticeable changes to our sleep architecture.
As we age, we typically see these changes:
- The total time we spend asleep each night decreases.
- Sleep latency (the time it takes to go from fully awake to asleep once in bed) increases.
- The amount of time spent in NREM-1 and NREM-2 (light sleep) stages increases.
- The amount of time spent in NREM-3 (deep sleep) decreases.
- We spend less time in REM sleep.
- We go through fewer sleep cycles each night.
- The efficiency of our sleep diminishes.
- Phase advance of the circadian rhythm occurs (meaning early to bed and early to rise).
- Daytime napping frequency increases.
For a more in-depth look at seniors sleep, see our guide Sleep and Aging: Safe Sleeping Guide for Seniors.
It’s About Quantity and Quality — Why Deep Sleep and REM Sleep Matter
Ideally, when we sleep, we want to be getting all the benefits that come from experiencing uninterrupted sleep cycles through the night, where we experience both NREM-3 “deep sleep” and REM sleep.
Sure, you may get between 7-9 hours of sleep. But if it is fragmented sleep (meaning it is interrupted by brief arousals) due to a sleep disorder or any other reason, then the quality of your sleep will suffer. You may suffer the effects of poor-quality sleep, such as daytime fatigue, despite appearing to be getting enough sleep.
Experiencing the deep sleep of the NREM-3 stage is crucial since this sleep stage is where your body’s restorative work happens — where physical recovery, restoration, and growth happens.
What Happens If I Don’t Get Enough Deep Sleep?
Not spending enough time in the NREM-3 sleep stage (deep sleep) puts individuals at increased risk of suffering chronic diseases such as cardiovascular disease, diabetes, obesity, and depression.
Daytime fatigue due to insufficient sleep can cause problems with mood, concentration, cognitive function, and increased risk of accidents and injury, especially in the workplace and when driving.
Rapid Eye Movement (REM) sleep is the final stage in the sleep cycle, coming after the NREM-3 stage, where we experience deep sleep.
Getting an uninterrupted night’s sleep is important as the length of time spent in REM sleep increases in later sleep cycles; sleep cycles earlier in the night have shorter REM stages.
REM sleep is where the brain processes memories and emotions and is central to our ability to learn and remember.
Signs You’re Not Getting Enough Sleep
Daytime tiredness is one obvious sign that you may not be getting enough sleep, but what are some of the other things to look out for that may suggest you are not getting the recommended hours of sleep for your age?
Other signs include:
- Falling asleep very quickly after going to bed.
- Feeling groggy upon waking and finding it difficult to get out of bed.
- Needing an alarm clock to wake up in the morning.
- Becoming drowsy after a large meal or while driving.
- Falling asleep in the evening before going to bed, for example, while watching T.V. or reading.
- Becoming sleepy when in warm environments or while sitting in class or meetings.
If you’re noticing any of these signs in your own life, perhaps it’s time to take a look at your mattress. Not having the right mattress for your needs is one of the biggest culprits of disturbed sleep.
In our ultimate guide to choosing a new mattress, we show you the nine signs to look for that may mean you should be thinking about replacing your mattress.
What Are The Negative Effects of Not Getting Enough Sleep?
According to a consensus statement by the Journal of Clinical Sleep Medicine, sleeping less than the recommended number of hours per day can result in adverse health outcomes such as:
- Weight gain/obesity
- Heart disease
- Increased risk of death
Beyond developing potentially serious negative health conditions, sleep deprivation can have effects that can affect your everyday life, taking a toll on relationships, professional life, and education:
- General irritability and moodiness
- Lack of sex drive or interest in sex
- Problems with concentration, memory, and learning
- Diminished ability to problem-solve
- Reduced creativity
- Premature aging — especially skin
- Impaired motor skills
- Increased risk of accidents
- Susceptibility to minor illnesses like colds and infections due to a weakened immune system
Debunking Myths About Getting the Right Amount of Sleep
🦄 Myth: Sleeping in on the weekend allows you to “catch up” on sleep.
🤔 Fact: Getting an extra couple of hours of sleep on the weekend may provide some temporary respite from fatigue, but chronic sleep debt cannot be “caught up” on in this way.
Developing a new healthy sleep routine that means you get the right number of quality sleep hours consistently is the only way to effectively “repay” any sleep debt incurred.
🦄 Myth: Missing only an hour of sleep here and there won’t have any detrimental effects.
🤔 Fact: It may not be evident at the time, but missing out on an hour or two of sleep can have unnoticed effects like the inability to think quickly and having a diminished reaction time.
Consistently missing out on an hour or two of sleep, even if sporadic, can have longer-term effects and put you at higher risk of developing certain diseases and other health conditions.
🦄 Myth: Sleeping longer will solve any fatigue problems.
🤔 Fact: As we’ve already seen, sleep quality matters just as much, if not more, than sleep quantity. Even if you are sleeping the recommended number of hours each night but not experiencing NREM-3 and REM sleep, you will likely not notice any improvement in daytime fatigue.
🦄 Myth: You can adjust quickly to a new sleep schedule.
🤔 Fact: Whether due to shift work, traveling between time zones, or just to develop more healthy sleep habits, sometimes a change in sleep schedule is necessary.
However, it is impossible to make drastic changes quickly — changing your sleep schedule means changing your biological clock, which can take a week or longer to adjust to new sleep hours.
This article aims to show the importance of getting the right number of hours of good-quality sleep and that the number of hours needed is different for different age groups.
Here are the most important takeaways:
- Age matters. Newborns and young babies require the most sleep over a 24-hour period, and this need diminishes as we age. The average adult, from the age of 18 up, requires 7-9 hours of sleep per night.
- Our sleep architecture changes as we age. The length of our sleep cycle changes drastically from the time we are born to our adult years; the adult sleep cycle lasts anywhere between 2-3 times longer than a newborn. Adults spend 20-25% of sleep time in REM sleep; babies spend approximately 50% of their time in REM sleep.
- The circadian rhythm takes time to develop. It usually takes 3-4 months for the circadian rhythm to become entrained in babies, which is why newborns and very young babies sleep throughout the entire day and not for long undisturbed periods.
- We sleep less as we age. We experience decreased sleep efficiency, experience fewer sleep cycles per night, spend less time in deep and REM sleep, and more time in the lighter sleep stages (NREM-1 and NREM-2).
- Quality as well as quantity matters. Uninterrupted sleep that allows full sleep cycles with time spent in both deep and REM sleep within the number of recommended hours is optimal for health and peak performance.
- Not getting enough good quality sleep is terrible for your health. Operating on a chronic shortage of sleep puts you at an increased risk of potentially serious and life-shortening health conditions. Both your physical and mental health can suffer, and not getting enough sleep can affect your everyday life in many harmful ways.
- One final recommendation: Having the right mattress that suits your personal needs is the single best investment you will make when it comes to getting enough good quality sleep. Our Best Mattress guides will show you how to pick the bed that’s the right match for you.