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June 14, 2022

The pressing question: how many hours to sleep?

The pressing question: how many hours to sleep?

A quick check on Google shows more than 230 million results for searches on the ideal amount of time we should sleep. Considering this and popular culture, we… go nowhere, because we’ll get many different answers. But then… how many hours should we sleep?

If you clicked on this post expecting an exact number that came out of a complex magical formula, you may think you didn’t find what you were looking for. But everything can be explained, even why there shouldn’t be an exact answer for “how many hours should we sleep?”.

Let’s explain.

How many hours should we sleep daily?

The amount of sleep a person needs depends on several factors, including age, genetics, health conditions, sports practice, medication intake and accumulated tiredness, among many other variables.

On average, an adult person needs between 7 and 9 hours of sleep a day. Here, adult means aged between 18 and 64.

This conclusion comes from the US National Sleep Foundation, who gathered specialists from different fields to analyze the existing literature on sleeping time.

The study divided recommendations on sleep time in nine age groups, from birth until old age. On the table below you’ll find the recommended sleep time for each group. The table also includes acceptable sleep time and non-ideal sleep time, but this can vary depending on each person.

Recommended hours of sleep by age group and acceptable hours of sleep by age group according to the National Sleep Foundation

Note that these numbers can vary from person to person, as there are the so-called “long sleepers” and “short sleepers”, who have different sleep hour needs.

The ‘lie’ of advising to sleep 8 hours a day

Lie is too strong a word but using 8 hours of sleep as the universal standard is a distorted view of reality.

From the age of 14, sleeping 8 hours a night can be considered within the acceptable standard, but while this is the minimum limit for younger people, it is the maximum recommended for older people.

Knowing how many hours we should sleep is an individual matter, and it is not the only quality standard for bedtime. Sleep regularity is just as important as quantity. Other parameters of a good night are:

  • Sleep latency – It doesn’t take you more than half an hour to fall asleep;
  • Night awakenings – You wake up at most once a night;
  • Quick return to sleep – When you wake up in the middle of the night, you go back to sleep within 20 minutes;
  • Efficiency – You spend 85% of your time in bed sleeping.

But knowing all this is impossible. For example, how many times you wake up in the middle of the night. Often, it’s just micro-awakenings that get in the way of sleep phases, but they are too short to be remembered. This, for example, is what happens to patients with sleep apnea.

Additionally, there is no way to measure sleep latency without using technology. After all, there is a transition between being awake and sleeping, when we do not know for sure if we are here or there.

For this, there are devices that monitor sleep and show you this (and other) data in apps or websites. Some of these ‘sleep trackers’ have the same result accuracy as medically valid exams.

Persono’s technology, for example, has been tested and is recommended by Team Brasil and COB, the Brazilian Olympic Committee. Do we need to say more?

To learn more about our pillow with Persono technology, visit the website:

How much sleep does a person need?

The table of recommended sleep time is just a guide that helps you understand the quality of sleep, which is why the times are shown in periods, some of them rather wide.

To understand how much sleep you need, you should consider factors such as health, stress levels, and even current sleep patterns. A sudden change in patterns, even with the same number of hours, can completely change the way a person wakes up.

You can only assess sleep quality accurately with a polysomnography, but by answering a few questions you can get a very clear idea of ​​whether you are getting enough sleep.

  • Do you feel good and energetic when you wake up with the time you currently sleep?
  • Do you have a chronic illness or temporary health condition that could change your sleep patterns?
  • What medications are you taking?
  • Are you able to perform your activities, including intense work and physical exercise, with enough energy?
  • Do you rely on caffeine or other energy substances to get you through the day?
  • Do you have a regular routine?
  • Are there any sleep problems in your medical history?

Once you have answered these questions, you will be able to identify and adjust your sleep time. Good night!

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