Bedtime: How to Determine the Optimal Amount of Sleep

Getting enough sleep is essential for our health and performance. And that depends largely on the quality of our sleep, which can be influenced by various factors. One of these factors is our bedtime and the duration of our sleep.

If these are optimally tailored to our sleep type, they can help ensure that we get enough rest at night and wake up feeling energized in the morning. In this article, we’ll provide you with the most important information on what the perfect bedtime entails and how you can determine the right time to wake up for you.

Going to bed at the “perfect” time in the evening is often not as easy as it sounds. Either your thoughts are circling around personal and work-related problems, there are still so many things on your to-do list, or your new favorite TV show is just getting so exciting. Yet it’s precisely the distractions from smartphones, tablets, TVs, and the like in the bedroom that cause bedtime to keep getting pushed back further and further. The reason for this is the blue light emitted by these devices, which inhibits melatonin production.

Melatonin, also known as the sleep hormone, is an important natural mechanism that helps prepare our bodies for sleep and makes us feel tired. A regular sleep-wake cycle—which includes going to bed at the right time—can help us get enough sleep and start the next day feeling energized.

However, there is no one-size-fits-all “best” bedtime for everyone.

After all, when we should go to bed also depends on chronotypes and life stage. Babies and toddlers have a much greater need for sleep than adults and therefore different bedtimes. And even among them, a distinction must be made between younger adults and seniors. This is because as people age, they often have a reduced need for sleep and can get by on just 5 to 6 hours of sleep per night. Seniors, however, often make up for lost sleep with an afternoon nap

If we align our sleep rhythm with the stage of life we’re in, it can have an extremely positive impact on sleep quality. After all, the consequences of too little sleep can be quite burdensome, ranging from constant irritability, poor concentration, chronic exhaustion, and reduced performance to obesity and increased susceptibility to infections

Ideally, adults should go to bed between 9 p.m. and midnight. This gives you the opportunity to wake up to the light of the rising sun after an optimal recommended sleep duration of 7 to 9 hours, which in turn has a positive effect on your mood and helps you feel refreshed.

However, you can determine the exact time you should go to bed based on your chronotype. A chronotype refers to a person’s individual sleep rhythm. The main distinction is between owls and larks. While there are also mixed types combining these, and additional types have since been defined, science primarily works with the lark and owl sleep types.

But what defines these types, and how do their sleep patterns differ? Larks like to go to bed early in the evening and have no trouble getting out of bed in the morning. Night owls, on the other hand, don’t settle down until late. They prefer to turn night into day and remain creative and productive even in the evening and at night—which is why they find it so hard to get up in the morning.

So, going to bed at 9 or 10 p.m. feels completely normal for larks, while owls would still be tossing and turning for hours if they went to bed at that time. The good news: Night owls don’t have to force themselves to go to bed early. As long as they’re in bed by midnight at the latest, they’ll still get enough sleep and can wake up with the morning light the next day.

However, if you go to bed much later than midnight, you might be in deep sleep when it gets light in the morning and you’re woken up by the sun. This throws your internal clock out of balance and makes you feel like you have a hangover when you get up. Not the best conditions for a good day.

Children and teenagers, on the other hand, have different sleep needs than adults. While newborns still need about 17 hours of sleep a day, teenagers need 8 to 10. In addition to their school obligations, they also have to cope with hormonal changes. A lack of sleep can really throw teenagers at that age off track. Younger schoolchildren, who need to process and store a lot of what they’ve learned during the night, should aim for 9 to 11 hours of sleep. Bedtime should therefore ideally be based on when school starts the next morning.

You can calculate the optimal bedtime for your sleep needs using a very simple formula, ensuring that you aren’t jolted out of a deep sleep phase when your alarm goes off. All you need to do is figure out in advance how much sleep you need each night to feel refreshed the next day. Tip 2 in the previous paragraph can help you with this.

The calculation is based on the assumption that it takes an average person about 15 minutes to fall asleep and that they go through 5 to 6 sleep cycles per night, each lasting 90 minutes. Ideally, that adds up to between 7.5 and 9 hours of sleep. Ideally, you’ve already determined your sleep needs and figured out whether you feel more refreshed after 5 or 6 sleep cycles. To do this, take the time you need to get up in the morning and count back the time required for 5 or 6 sleep cycles.

Calculation example: Your alarm goes off at 6 a.m. A night with 5 sleep cycles consists of about 450 minutes, or 7.5 hours. Subtracting the 15 minutes it takes you to fall asleep, you’d need to go to bed at 10:15 p.m. to complete all the cycles and avoid being woken up during deep sleep.

You could also go to bed at 11:45 p.m. or 1:15 a.m. Your sleep duration would then naturally be shorter. However, as long as you still wake up feeling refreshed, your sleep need has apparently already been met.

How much sleep a person needs and when they should ideally go to bed varies greatly from person to person. For a healthy sleep-wake cycle, it’s definitely recommended to listen to your body’s signals and live in harmony with your internal clock.

After all, it tells us exactly how much rest we need and when we need it. If you’re always very tired in the morning after getting up and don’t feel rested, that could be a sign that you need more sleep.

Now you should start by trying to adjust your bedtime and ensure you get the best possible sleep quality.