What Determines How Much Sleep You Need?
Brianna Sharp

Have you ever realized someone you know needs 9 hours of sleep per night while you only need 6? If you have, you’ve certainly come to the right place, because in this blog, I’m going to be explaining the various factors that determine how much sleep people need. Let’s dive in!

Factors that Determine How Much Sleep People Need


First and foremost, age greatly impacts the amount of sleep people need. On average, newborns (0-3 months) need 14-17 hours, infants (4-11 months) need 12-15 hours, toddlers (1-2 years) need 11-14 hours, preschoolers (3-5 years) need 10-13 hours, school-age children (6-13 years) need 9-11 hours, teenagers (14-17 years) need 8-10 hours, adults (18-64) need 7-9 hours, and older adults (65+ years) need 7-8 hours of sleep per night. Younger people typically need more sleep because they are growing, both physically and mentally. However, each person is different, and each individual’s sleep needs are unique.


Genetics also greatly impact the amount of sleep that people need, and this is because certain genes are linked to sleep-related traits, such as duration and quality of sleep. Studies have identified genes that influence the circadian rhythm, and the variation in these genes has the ability to influence sleep patterns, such as causing people to be more prone to early-morning awakening or evening alertness. Genetics also influence sleep disorders like insomnia and sleep apnea, which are both influential in affecting the amount of sleep that people get and the quality of it.


Another factor that determines how much sleep people need is lifestyle. Individuals who have physically and mentally challenging jobs may need more sleep at night than those who don’t. This is because their body and brain need additional time to rest and reset. For that same reason, those who suffer from conditions such as chronic illnesses or mental health disorders may also need more sleep.

Sleep Quality

The quality of sleep that people get has a strong impact on the amount of sleep that they need. As you can imply, those who don’t get very good quality sleep may end up feeling tired and fatigued, and may need to sleep for longer to get an adequate amount. With this in mind, those who suffer from sleep disorders like insomnia and sleep apnea may also need more sleep, and this is because their sleep quality may not be as good.


Last but not least, the environment in which people sleep is a factor that determines how much sleep they may need, and this is because people’s environment affects their sleep quality. If someone’s sleeping in an environment that’s noisy and bright, they may not get as good of sleep as someone else who’s sleeping in a quiet and dark environment. As you can imagine, that person who’s sleeping in the noisy and bright environment may need more sleep, as they may not be getting as good of quality sleep.

Closing Remarks

There are various factors that impact the amounts of sleep people need. These include, but aren’t limited to age, genetics, lifestyle, sleep quality, and environment. 

So the next time you’re with someone and you realize they slept for much shorter or longer than you, take these factors into account! You may be able to understand why there was a difference in the amount of sleep the two of you needed.

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