Home / Advice / How Much Deep Sleep Do You Need: A Better Understanding of Sleep

How Much Deep Sleep Do You NeedNo matter how hard you keep up with the demands of those tight schedules at work, you still often end up sacrificing on your sleep to get through them. Also, we often experience interrupted sleep, especially when we are stressed or anxious. Unfortunately, most of us are unfamiliar with the stages of sleep that is why we live by one rule which is to get some sleep at least daily. That is quite dangerous since there is actually a standard as to how much deep sleep do you need to have a healthier life.

The most obvious downsides on cutting down on sleep, especially deep sleep, are that it takes a toll on your health, energy levels, your mental sharpness, mood as well as the ability to handle your stress levels. As bad as these sound, these are just the short terms effects. The long-term effects of it will wreak havoc not only mentally but also physically. However, there is something called oversleeping too which is equally bad for your health. Hence, in this article, we aim to give you a better understanding of sleep.

What is Sleep: A Deeper Look

Going to sleep is not just a time for your body to shut down. While you sleep, the brain remains busy as it oversees the biological maintenance of your body so that it runs in perfect condition. It also prepares you for the day when you wake up. Not having the adequate amount of sleep will not allow your body’s energy to be fully restored. While you may continue to get through your day, it will not be to the fullest potential of what you are capable of.

Stages of Sleep

When we sleep, we follow a pattern. That is alternating between rapid eye movement (REM) and non-rapid eye movement (NREM) of sleep every night. It is a cycle that every after 90 minutes, it will repeat itself. Let’s break it down further for you.

NREM- 3/4th of our sleep

  • First Stage: This is where you are relaxed and shut your eyes for the night. Twitching is frequent at this stage, and you can be easily awakened as well.
  • Second Stage: Here, you start to get more disengaged from all the surroundings, and the body temperature drops too.
  • Third Stage: This stage is the deepest and restorative part of your sleep. It is difficult to awaken someone in this stage of sleep, and if you do, you will be disoriented and groggy.

REM- 1/4th of our sleep

  • After we fall into deep sleep, we go back to the second stage before we enter the REM sleep. About 50% of our sleep time is spent in the second stage and about 20% in REM sleep. The remaining 30% covers all the other stages of sleep.

How Much Deep Sleep Do You Need: Sleep Quantity and Quality

Deep sleep is the most important part of any sleep cycle. This is mainly where the body is able to repair itself and also build new energy for the day ahead. It is also where growth hormones are released in children and young adults, and what aids in the maturation process of the body. Additionally, deep sleep allows the body to repair tissues and detoxify itself.

To put it in numbers, an adult over the age of 18 years will need anywhere about 1.5 to 2 hours of deep sleep. This is about 20% of your whole sleep. Since this is a natural pattern, the best way to increase your hours of deep sleep is you must also have improved sleep quality and quantity. Of course, quantity refers to the number of hours spent sleeping. Sleep quality, on the other hand, refers to a sleep that is peaceful or uninterrupted.

Sleep would do you no good if the quality of your sleep is poor even if you slept for more than eight hours. When you have a poor sleep quality, you will often find yourself feeling quite tired. Conversely, there are studies that claim that if your sleep quality is fantastic, then you will be able to manage on even fewer hours of sleep.

A combination of short sleep duration and poor quality of sleep are majorly responsible for several negative effects that are sleep related, one of the most common ones being sleep apnea. Hence, never just focus on the amount of sleep but also the quality of your sleep. In fact, some experts even say too much sleep can also be dangerous.

The Effects of Oversleeping

Anywhere between a total of seven and nine hours of sleep is perfect for our well-being, but what if you go beyond nine hours? Of course, we are not talking about those extra hours you sleep on the weekend because those do no harm. However, if you sleep beyond nine hours on a regular basis, then that is a cause for concern.

Depression is considered amongst the most common causes of oversleeping along with issues like cognitive impairment, increased inflammation and so on. Just like sleeping less, oversleeping messes with your circadian rhythm which is a 24-hour cycle and is driven by our biological clocks which results in all the changes in our physical and mental health as well as our behavior.

When we oversleep, we end up throwing off this rhythm which results in feelings of fatigue, lethargy, and drowsiness. This completely confuses the human body, and this feels very similar to a jet lag. People who oversleep often tend to complain about having headaches through the day. It also has an effect on certain neurotransmitters in our brains, serotonin being one of them. It is essential to know that oversleeping could also be a medical condition in people called hypersomnia and its best to visit a physician in cases like these.


As mentioned earlier, you should try to focus on the quality of your sleep since it will directly affect your physical and mental well-being. This also affects the quality of your life when you are awake, your productivity levels, heart and brain health, the immune system, your weight and several others. As to how much deep sleep do you need, it is ideally at least 20% of the total hours you slept.