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Deep sleep - What Is It And Are You Getting Enough?

Updated: 19/08/2022
14 Min
Simon Igild
Simon Igild

Deep sleep - What Is It And Are You Getting Enough?

Updated: 19/08/2022
14 Min
Simon Igild
Simon Igild

Table of Contents


Like eating and exercising, sleep is essential for your health. There are five stages of sleep (4 sleeping and one-half awake), and each stage has a specific purpose. In order to feel at your best every day, you need to get enough restful, therapeutic sleep. Because of the potential consequences of not getting enough deep sleep, it is crucial to understand what deep sleep is, its benefits, and the signs of not getting enough deep sleep.

Deep sleep is the deepest stage of sleep, and it's important for physical health, mental health, and overall well-being. Your body can heal and repair itself during deep sleep, so it's crucial to make sure you're getting enough.

As we all know, sleep is essential for our health. However, many misconceptions exist about what happens when we don't get enough deep sleep. This article will explore some of the consequences of a lack of deep sleep and how it can affect you in the long run.


What are the different sleep stages?

There are four sleep stages plus an awake stage: Awake, N1, N2, N3, and REM sleep. 

The first stage, Awake, is not considered a sleep stage because you are not truly asleep.

NREM sleep (non-rapid eye movement) is classified as stages N1–N3, with progressively more deep sleep in each stage.

The NREM stages account for approximately 75% of total sleep time​1​, with the N2 stage accounting for the majority of total sleep time.

A typical night's sleep consists of four to five sleep cycles, with the stages of sleep proceeding in the following order: N1, N2, N3, N2, REM.

A complete sleep cycle lasts approximately 90 to 120 minutes.

The first REM period is brief, but as the night goes on, longer REM periods and less time in deep sleep (NREM) occur. 


The first stage is the wake stage, also known as stage W, and it is determined by whether the eyes are open or closed. 

N1 - (Stage 1) Light sleep ( 5% of total sleep)

Stage 1 is a light sleep state in which surroundings can quickly awaken the sleeper. This stage lasts for about 1 to 10 minutes, and then the brainwaves become more synchronized with each other, and the sleeper enters N2.

N2 - (Stage 2) Deeper Sleep (45% of total sleep)

You will enter a deeper sleep state as your heart rate and body temperature decrease. Stage 2 is a deeper sleep state where the sleeper is unaware of their surroundings. Stage 2 sleep lasts approximately 25 minutes in the first cycle. It gradually increases in length with each subsequent cycle, eventually accounting for roughly 45 percent of total sleep.

N3 - (Stage 3) Deep Sleep (25% of total sleep)

Deep Sleep is also known as SWS. 

Slow-wave sleep (SWS)​2​ is the deepest phase of non-rapid eye movement (NREM) sleep. Stage 3 sleep, the deep sleep stage is the most challenging stage to awaken from; for some people, even loud noises (greater than 100 decibels) will not wake them up.

People tend to spend less time in deep sleep and more time in stage 2 as they age. Deep sleep is the stage during which the body repairs and regrows tissues, builds bone and muscle, and fortifies the immune system.

Sleepwalking, night terrors, and bedwetting are also common at this stage. 

REM Sleep - Stage 4 (25% of total sleep)

The next stage is called REM or Rapid Eye Movement Sleep, where brain activity increases markedly. Dreams occur during this phase because it is when brain waves are most active and similar to wakefulness. This stage typically begins 90 minutes after falling asleep, with each REM cycle getting longer throughout the night.

The first period is usually 10 minutes long, and the last one can last up to an hour.

Dreaming and nightmares occur during REM. 

What is deep sleep?

Deep sleep, also known as slow wave sleep, is the deepest stage of sleep. Deep sleep is important for physical health, mental health, and overall well-being.

Deep sleep is the most important stage of sleep because it allows the brain to recover and repair itself.

Deep sleep helps people to wake up feeling more refreshed and energized.

Deep sleep is a state of the human brain characterized by slow-wave sleep.

There are two types of deep sleep: slow-wave sleep and paradoxical sleep. Slow-wave sleep is the deepest form of deep sleep, and it occurs in stages 3 and 4 of NREM. Paradoxical sleep, on the other hand, occurs in stage 1 or 2 of NREM.

Deep sleep is the most relaxing form of sleep that our body gets. It is also called the non REM sleep (rapid eye movement) stage of sleep.

Dreaming is frequently associated with REM sleep.

Approximately 80% of vivid dream recall occurs during the REM sleep stage. 

However, about 20% of dreams occur during deep sleep; they are not as vivid and frequently forgotten.

Vivid dream
A vivid dream illustration that could occur during REM sleep - Created by Luneeo

What is REM sleep?

REM sleep (rapid eye movement) is the last stage of the sleeping stages.

During REM sleep, our breathing is irregular and our eyes move rapidly in different directions. Our arm and leg muscles are temporarily paralyzed.

REM sleep is important for emotional health because it helps to process and consolidate memories.

REM sleep is also important for physical health because it helps to repair and regenerate tissues.

The function of REM sleep is not fully understood, but it is thought to be important for learning, memory, and mood.

It's common knowledge that REM sleep and dreaming go hand in hand, but why are we dreaming so much during the REM period is a more complicated subject.

Scientists believe that this is because the loss of muscle tone and reflexes during REM sleep, most likely serves an important function in preventing an individual from "acting out​1​" their dreams or nightmares while sleeping.

What is non-REM sleep?

Non-REM sleep stands for non-rapid eye movement, also known as NREM sleep.

NREM stages 1 and 2 are categorized as light sleep, whereas NREM stage 3 is categorized as deep sleep.

NREM stages 1–3 share characteristics such as the brain being relatively inactive, slowed breathing, reduced muscle activity, and reduced heartbeat.

Non-REM sleep can be divided into three stages:

Stage 1 is a light sleep stage in which you are still easily awakened. You may experience sudden muscle contractions or "jerks."

Stage 2 is a slightly deeper sleep stage in which you are harder to awaken and your heart rate slows.

Stage 3, also known as deep sleep, is the deepest stage of non-REM sleep. It is very difficult to awaken someone during this stage, and they may not even respond to loud noises.

During non-REM sleep, our breathing is regular and our eyes are closed. Our body temperature decreases and our muscles relax.

Non-REM sleep is important for physical health because it helps to repair and regenerate tissues.

Non-REM sleep is also important for emotional health because it helps to process and consolidate memories.

The function of non-REM sleep is not fully understood, but it is thought to be important for learning, memory, and mood.

What happens when you don't get enough deep sleep?

It's paramount to get adequate sleep at night since it promotes your body's growth and healing. But if you don't get enough deep sleep, there will be adverse consequences.

When you don't get enough deep sleep, your health can deteriorate over time and cause a range of problems. One problem commonly seen in people who don't get enough deep sleep is weight gain. Not getting enough deep sleep often causes people to overeat and crave unhealthy foods, leading to weight gain. This weight gain often leads to other health problems such as diabetes, heart disease, and high blood pressure, all of which are severe problems that can cause death if left untreated.

Signs that you are not getting enough deep sleep include:

  • Feeling tired during the day
  • Difficulty concentrating
  • Irritability or moodiness
  • Falling asleep during the day
  • Needing caffeine to get through the day

Benefits of deep sleep:

  • Helps repair and regenerate tissues and cells in the body 
  • Increases energy levels 
  • Reduces inflammation in the body, which can help against arthritis and other autoimmune disorders 
  • Helps regulate hormones that control appetite and weight 
  • Improves mood
  • Improved immune function
  • Lower blood pressure
  • Improved heart health
  • Increased growth hormone production (which helps with muscle growth and Repair)
  • Improved brain function and memory

How much deep sleep should you get?

Deep sleep is an integral part of the human sleep cycle. When the brain is inactive, the mind and body are at rest. 

The amount of deep sleep you should get varies from person to person. The key is to find out how much deep sleep you need and then take steps to ensure you get it.

The amount of deep sleep you need is determined by age, genetics, lifestyle choice, and even the time of day. For example, if you are a child or a teenager, your body may require more deep sleep than someone who is mid-life.

Many factors affect the amount of sleep you need. It's a good idea to consult your doctor to find out what's best for you.

How much deep sleep do adults need?

Deep sleep accounts for 13 to 23 percent of all sleep in healthy persons.

So, if you sleep 8 hours per night, that's 60 to 110 minutes.

The amount of sleep required by adults varies from that required by children and teenagers.

Adults require at least seven hours of sleep, but eight or nine hours is recommended. 

The National Sleep Foundation recommends that adults get 7-9 hours of sleep each night.

How much deep sleep do children need?

It has been suggested​3​ that by the time children enter school (typically at the age of six), they begin to exhibit​4​ circadian rhythm sleep phase preferences - an inclination to be a "night owl" or "morning bird."

However, older children are significantly more likely than younger children to have difficulty initiating and maintaining sleep.

Furthermore, older children are more likely to have nightmares, which usually disrupt sleep​5​, making it erratic.

According to one study, children appear to have longer REM sleep latencies than adults and thus spend a more significant percentage of their sleep time​6​ in the deep sleep stage(Slow-wave-sleep). 

A good night's sleep is essential for children's healthy development. It helps them grow, learn and stay healthy.

Sleep deprivation can lead to reduced cognitive function, decreased concentration ability, and increased irritability. Sleep also plays a vital role in developing a child's immune system.

How much sleep children need is determined by their age and can range from 10-14 hours per night. A child's brain needs more deep sleep than an adult's brain to develop correctly, so they need more time in bed at night.

Why is deep sleep important?

Deep sleep is the most essential part of your sleep cycle. It's when your body repairs itself, and your brain gets a break from processing all the information it was exposed to during the day.

Deep sleep is not only crucial for mental health but also for weight loss. You burn more calories when you are in a deep sleep, and your metabolism improves, causing weight loss.

During deep sleep, your brain releases hormones needed for healthy functioning, such as growth hormone and serotonin. Deep sleep also helps regulate your metabolism, immune system, blood pressure, and more.

Sleep disorders associated with deep sleep

According to the National Sleep Foundation, more than one-third of adults in the United States experience some form of sleep disorder.

The truth is, there are many sleep disorders, and they're all different. Some people have insomnia, which means they have trouble falling asleep or staying asleep. 

Others have chronic sleep deprivation, so they don't get enough sleep regularly. 

And some people have narcolepsy, which means their bodies just shut down in the middle of the day.

Narcolepsy​7​ is a neurological disorder that occurs when too many cells in the brain produce the neurotransmitter hypocretin. This leads to excessive daytime sleepiness, fragmented night-time sleep, and sudden muscle weakness.

Sleep apnea​8​ is a disorder in which the person stops breathing for short periods during sleep. This causes them to wake up throughout the night and not get enough quality sleep.

Restless leg syndrome (RLS)​9​ is a condition that causes an irresistible urge to move the legs. This can make it hard to fall asleep and stay asleep.

There are many other sleep disorders, but these are some of the most common. If you think you might have a sleep disorder, talk to your doctor. They can help you get the treatment you need to get deep, quality sleep.

Sleep deprivation 

Doctors say deep sleep disorders are becoming more common. They are also harder to diagnose because they don't have apparent symptoms.

Sleep deprivation can be caused by several things, including stress and anxiety, pain, and depression. Doctors also say sleep deprivation can be caused by common sleep disorders like obstructive sleep apnoea or restless leg syndrome. 

Moreover, medication can affect sleep patterns and circadian rhythms, leading to sleep deprivation. 

Symptoms you're not getting enough deep sleep

If you're not sure if you're getting enough deep sleep, there are some signs to look out for:

  • You feel tired during the day, even after a full night's sleep
  • You have trouble concentrating or focusing on tasks
  • You find yourself getting irritable or cranky more easily
  • You have a hard time getting out of bed in the morning
  • You often find yourself dozing off during the day
  • You have trouble staying awake while driving or watching TV

If you're experiencing any of these signs, it's important to talk to your doctor. They can help you figure out if you're not getting enough deep sleep and what you can do to change that.


10 tips for a good night's sleep and how to get more deep sleep?

Stick to a regular routine at night

In the evening, your body prepares to sleep. The aim is to make sure your body knows what to do and when to do it.

A good routine helps you fall asleep faster and sleep deeper.

A sleeping routine should include calming activities, such as reading a book or listening to relaxing music, followed by an activity that signals the end of the day, such as brushing your teeth or taking a bath.

Keep your room dark and quiet at night.

The room should be dark and quiet at night. This will help you get a good night's sleep.

First and foremost, the room should be dark.

Light from outside or inside the house can disrupt your sleep pattern and make it difficult to fall asleep.

Secondly, the room should be quiet enough for you to sleep peacefully.

Avoid anything that might divert your attention away from sleeping, such as loud neighbors or television shows. 

Make sure you don't drink too much coffee or alcohol before bed.

Knowing how much caffeine and alcohol you drink before bed is noteworthy. Drinking too much coffee or alcohol before bed can cause sleeplessness and other sleep problems.

Caffeine is a stimulant that blocks the sleep-inducing chemical adenosine, making it hard for your body to relax. Alcohol also disrupts the natural sleep cycle by slowing brain activity and reducing REM sleep (rapid eye movement).

Try progressive muscle relaxation techniques before bedtime.

There are many ways to reduce stress and anxiety. One of the techniques is progressive muscle relaxation.

Progressive muscle relaxation is a technique that involves tensing and relaxing different muscle groups in your body. It can be done by yourself or with the help of a therapist. The idea behind this technique is that it will calm you down and help you release tension, which in turn will improve your sleep.

The basic principle of progressive muscle relaxation is to move through your body, part by part. You first tense up your muscles. After that, you maintain the tension for a short while. After that, you allow them to unwind.

Many of us have a vague and ambiguous idea of what relaxation is. The concept of relaxation is vague and ill-defined. What does it really mean to feel at ease and relaxed in your body? How does it feel to relax your hand?

Let's try a quick experiment: try to pay attention to how your left hand is currently feeling. Can you tell whether your hand feels tense or relaxed just off the top of your head? If not, try clenching your hand to the maximum extent you can. For a moment, keep the tension in place and pay attention to how it feels. Release the tension after that, and pay attention to how the hand feels.

It is intended that by experiencing the contrasts, you will gain a deeper understanding of how tension and relaxation actually feel. Perhaps you didn't notice a significant difference when we conducted our small experiment. That is entirely common. It takes time to adjust to the exercise and get to know your body better. You now understand the rationale behind progressive muscle relaxation.

This technique is often used to manage chronic pain, anxiety, depression, insomnia, and stress-related health conditions.

Have a relaxing ritual before bed.

A relaxing ritual like taking a bath or reading can work wonders in helping you get to bed feeling relaxed and ready for bedtime.

Many people find that their sleep is worse than it has ever been.

This is because of the stress in their lives and the technology we are constantly surrounded by. The first step to getting a better night's sleep is to make a ritual before bed.

A relaxing ritual like taking a bath or reading can do wonders by helping you fall asleep faster and stay asleep longer.

Some people like to read a book, light incense, or do yoga. Others prefer a more practical approach and like to squeeze stress balls or use essential oils. But the key is to find what works best for you and practice it daily.

Limit screen time at night.

The blue light from screens interrupts your natural circadian rhythm, so try not to use screens right before bed (except to use them as part of your nighttime routine).

Many of us are guilty of scrolling through our phones or watching TV before bed. 

But what is the impact of this?

A study published in the Journal of Clinical Sleep Medicine found that people who used their phones or tablets within an hour of bedtime experienced more disruptions in their sleep and were less satisfied with their sleep quality.

The blue light from these devices can disrupt your natural circadian rhythm and melatonin production, leading to poor sleep. Put your phone and other devices away at least an hour before bedtime to avoid this.

Put an AI sleep assistant to work for you!

AI sleep assistants are a new way to get the right amount of sleep. They can help you fall asleep by providing an optimal mix of soothing sounds and pre-recorded messages.

Planning your day in advance is advantageous if you can easily fall asleep at night.

If you have trouble falling asleep at night, try planning your day in advance. This will help you sleep better and avoid feeling overwhelmed.

Planning your day in advance is not difficult and can help you get a lot done. You will feel less stressed and more accomplished if you plan your day before it starts.

Invest in a proper Mattress.

A good mattress is essential for a good night's sleep. Great beds provide comfort, support, and breathability for the sleeper's body type and weight distribution.

A mattress is an important factor in our ability to sleep well. Still, many overlook its significance and continue to use a mattress that does not provide adequate support and comfort.

A new mattress can be an expensive investment, but it can unlock your ability to sleep better.

Regular physical activity

Making time for physical activity is essential for overall health. Exercise helps reduce stress, boost the immune system, reduce chronic pain, and improve sleep quality. However, avoiding heavy exercise too close to bedtime is rudimentary, or it can make it harder to fall asleep.


Deep sleep is crucial for our overall health and well-being. It allows our bodies to heal and repair, boosts our immune system, and helps us feel rested and rejuvenated.

We hope that by now you have a better understanding of deep sleep and the importance of getting enough of it. We've outlined some tips to help you get started on improving your sleep quality, including creating a bedtime ritual, limiting screen time before bed, and using an AI sleep assistant.

Additionally, investing in a comfortable mattress and getting regular exercise can also improve our deep sleep quality. If you're still having trouble sleeping well, be sure to consult with your doctor.

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