What are the 5 Sleep Stages and Why are They Important?

February 21, 2019

How Much Deep Sleep do you Need?

Getting enough sleep is essential for the human body. Insufficient night rest can lead to fatigue, lack of concentration, and ultimately more serious conditions like cardiovascular disease. Read more to find out what sleep stages there are, and why the deep sleep stags is especially important in order to stay healthy.

Fixed Rhythm

The human body sleeps at a fixed rhythm with different sleep stages. Each is recognizable by a typical brain wave pattern. The architecture of our sleep determines whether we sleep well or not.

A good night’s sleep includes the following five stages of sleep:

Stage 1: Sleep-in Stage

At this stage, the body relaxes and calms down more and more. Breathing becomes deeper and the pulse slows down. Many people experience this sleep stage, which is perceived in a dream-like way, as a time of falling or getting more and more “heavy”. Since sleep is still very superficial at this time, even small disturbances can cause us to wake up. Eating before bed, too much caffeine, bright lights, drinking alcohol, and general anxiety can disturb sleep at this point. As a result, you are more prone to sleep disturbances.

Stage 2: Light Sleep Stage

In the second stage of sleep, brain activity is limited to low frequencies. The muscles are relaxed, we sleep almost without any eye movements, and the transition to the restful sleep stages begins. Sleep research previously assumed that only deep sleep is important to memory formation. It is now known that even light sleep stages are important for processing information, and are therefore just as important for learning.

About half of the total sleep is spent by humans in the first two stages of sleep. Even in the light sleep stage, sleep is still superficial, so that small stimuli, sounds, or other disturbances still wake us up quite quickly. Here, too, sleep problems are often caused by stress.

Stages 3 and 4: Deep Sleep Stage

At this stage of sleep, which is divided by sleep researchers into a stage of moderate sleep and one of very deep sleep, we recover particularly well. We sleep deeply. The heartbeat and breathing rate slows down and the blood pressure drops. Our brain and muscle activity is kept to a minimum and we breathe rhythmically.

Many people are very difficult to wake up during the deep sleep stage. For mental and physical recovery, the most precious time begins at night. That’s why it’s so important to get a full and restful night's sleep. The proportion of deep sleep is very high at the beginning of the night, but decreases during sleep.

Those who drink too much alcohol or have sleep apnea hardly reach this deep sleep and often suffer from sleep disturbances.

Stage 5: Rem-Stage

The deep sleep stage is followed by a short light sleep stage, which leads directly into the REM sleep stage (also called the "dream sleep stage.") Many researchers assume that during this time, we process information and emotional impressions. Characteristic of REM are the fast eye movements under closed eyelids. REM is the abbreviation of the English term “rapid eye movement”. At this stage, brain activity accelerates significantly and heart rate increases. Breathing is shallow and fast.

Since we dream a lot at this stage, we could actually carry out movements (sleep walking). We also dream in other deep sleep stages, but in the REM-Stage it is longer and more intense. Although we dream, it is still easy to wake up during this sleep stage. Disorders at this stage can lead to difficulty concentrating and reduced learning capacity.

The Sleep Stages are Repeated Several Times in One Night

If we are healthy, the sleep stages are repeated five to six times a night. A complete stage cycle takes about 90 minute or more, or less than 10 minutes. At the beginning of the night, deep sleep dominates. Only in the second half of the night, and towards the end of the night, the REM stages are extended and the body prepares to wake up. Our sleep behavior during the stage cycles is like a staircase: first light sleep, then deep sleep, and at the lowest level the REM sleep stages.

How Much Deep Sleep Should You Have?

You should spend 20 - 30% of your total sleep in deep sleep in order to stay healthy. If deep sleep is shortened, for example due to insomnia, health issues may occur.

Why is Deep Sleep so Important and What Factors Influence It?

In deep sleep, the brain emits delta waves. They allow the brain maximum rest. Our body is also completely relaxed. During deep sleep, the body releases growth hormones that stimulate the strengthening of the immune system and reparation of cells to stay healthy. In addition, metabolism is regulated at this stage.

We need this absolutely relaxed stage, where the level of the stress hormone cortisol is lowest, in order to regenerate our immune system, strengthen our performance, and adequately recover.

In deep sleep stages, a transfer of things that you learn and experiences you have go from short-term to long-term memory. A good, healthy sleep depends on the quality and length of the deep sleep stage.

Factors that affect deep sleep and often cause sleep problems:

  • Old age
  • Stress
  • Noisy atmosphere
  • Bright sleeping environment
  • Irritability
  • A bed that is unsuitable
  • Excessive alcohol consumption
  • Coffee in the evening
  • A full stomach

How Can I Improve Sleep Quality and Sleep Healthy?

A good bed, which is individually adapted to the sleep needs and the physique of the person, is critical to reach the deep sleep stage, and is the basis for being able to sleep well. This is why we use linseed oil for our beds. It emits a pleasant aroma and is non-toxic. When we start designing here at Quagga Designs, our aim was and is to eliminate any metal parts. Although it is not scientifically proven, we believe that there might be a correlation between cancer and the electromagnetic fields given off by metal parts (if you are interested, you can read more about the metal beds and the possible side effects here).

Consistently going to bed and waking up at the same times is important to getting your body into a consistent sleeping routine. People who are exposed to a lot of stress in everyday life often suffer from sleep disturbances and sleep problems. For them, it is important to relax as much as possible before going to bed.

Getting a good bed, the right duvet, pillows, and bed linen play an important role. All of these elements combined together contribute to a restful and healthy night’s sleep. Care should be taken when choosing the right beds.

If you are not sure which bed is right for you, give us a call at 905.324.2098 or email me at hello@quaggadesigns.com.