This post was last updated on November 26th, 2018.
You may wonder how many hours a day is enough to sleep. Sometimes you feel tired after sleeping for 10 hours and sometimes you are refreshed after only 6 hours in bed.
The truth is – nobody can tell you with 100% certainty. There’s a lot of variables which play a role in a recommended dose of sleep. However, based on a lot of research we can take a look numbers for recommended sleep for an average person.
A sleep need in numbers
An average adult needs anything between 6-9h every day, with roughly 7.5h to be a safe “middle ground” value that we can recommend. This also perfectly corresponds to an average of 5 sleep cycles of 1.5h (if you want to know more about sleep cycles, read our article How to Wake Up and Be Fresh in the Morning). This means that for an average adult person, roughly 7.5h of a nigh sleep tends to be the best option.
However, toddlers and pre-teenage kids need to sleep more. Anything below 10h a day might have consequences in the future, as children develop most of their brain within the first 6 years of their life. This doesn’t mean that children that fall into this category should sleep a continuous block of time. It’s completely ok to split this amount of sleep into multiple chunks, for example, a night sleep and an afternoon nap.
Elderly people generally require less sleep and their sleep pattern is also a little shifted in comparison to adults. They go to bed earlier and wake up earlier in the morning too. An average older adult (>65 years old) requires roughly 7h of sleep.
Look at the following table compiled by National Sleep Foundation and see where you fit.
Consequences of not sleeping enough
Do you think that you can go just about right even with less sleep?
You might think that the suggested sleep times might not apply to you – all in all, we were discussing an average person sleep time and you don’t feel like an average person, are you? So as it is important to clarify the recommended sleep length times, it equally important to look at the other side of the coin – what is that you might lose if you don’t sleep enough. Here we might get some help from a professor of neuroscience and psychology at the University of California, Matthew Walker. He says in his book Why We Sleep the following:
Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer. Insufficient sleep is a key lifestyle factor determining whether or not you will develop Alzheimer’s disease. Inadequate sleep—even moderate reductions for just one week—disrupts blood sugar levels so profoundly that you would be classified as pre-diabetic.
As you can see, underestimating the power of good sleep can have serious consequences for your future life. Look at our other articles about healthy sleep or various alarm clocks that can help you with achieving the sleep goals for you and your family.
 Walker, Matthew. Why We Sleep: The New Science of Sleep and Dreams (p. 3). Penguin Books Ltd. Kindle Edition.