Understanding the 5 Stages of Sleep and Sleep Cycles

July 07, 2019

Understanding the 5 Stages of Sleep and Sleep Cycles

Sleep is the most important factor for our mental and physical well-being. There is a biological clock in every living cell. Sleep is more essential than food for life. Animals die of sleep deprivation before starvation.

Sleep Process

To start sleep process, pineal gland in the brain pumps melatonin. Then brain shuts itself to outside stimulus and turns inward. When we are falling sleep, short and strong contractions of the body parts start. Brain cells begin processing and registering daily information. Our immune system gets boosted during the good night sleep.

sleeping woman


5 Stages of Good Sleep 


It is the first 5 minutes of shallow sleep. There is no significant change in body the body yet.



Deep parts of the brain send electrical signals to knock down the cortex of the brain. The higher amount of these electrical signals predicts better performance for the next day. At the molecular level, memories are created or reinforced during this stage. It could last up to 50 minutes.

sleeping couple



The deep, coma like stage, which is essential for brain to recuperate. The cells start producing growth hormone which is essential for bone and muscle health. It makes you feel vibrant and healthy. Pain receptors become inactive. This is the stage you won’t easily wake up.



The muscles are fully relaxed, mental activity almost stops. The brain activity form is similar to coma patients. It could last up to 30 minutes.

The Stages 1 - 4 are repeated before going to REM stage of the sleep. The whole cycle is repeated 4 - 6 times before we wake up.

sleep stages cycles



This stage is the most critical stage for survival. Rodents deprived of REM sleep die after just 5 weeks. Mostly 20 - 30% of a night's sleep is REM session in adults. Fifty percent (50%) of newborn’s sleep is REM sleep.

Distinctive eye movements, engorgement of sexual organs happen in this stage. Dreaming takes place in this phase. It is believed that everyone dreams but some don’t recall it. Body becomes unable to regulate temperature and blood pressure in REM stage. But it is not coma-like stage as Stage 4. Brain stays fully active in REM stage. The muscles in the eyes and ears are activated, the eyeballs move from side to side. Systems in the brain stem are completely shut down. Serotonin production stops in this stage.

End of REM Stage is marked with brief wakening. When light comes through eyelids and touches retina, wake-up signal is sent to the brain.

sleep stages in box form



  Author: Dr. Tina Ureten

Also in Blog

Stats & Facts About Sleep (Infographic) - Part 2
Stats & Facts About Sleep (Infographic) - Part 2

January 14, 2020

Along with proper nutrition and regular exercise, sleep plays a major role in our health. With this compilation of interesting facts and statistics about sleep, we hope you will gain insight and recognize the importance of sleep in your daily lives. The significance of the positive, as well as negative effects of sleep, should not be ignored, or taken for granted.

View full article →

Did You Know Info Series - Jan 2020
Did You Know Info Series - Jan 2020

January 13, 2020

Did you know ... that humans are the only mammal that willingly delays sleep? Did you know ... that laughing can increase blood flow by 20%? Did you know ... that tea can lower risks of heart attacks, certain kinds of cancer, and type 2 diabetes? Did you know ... that yoga can boost your cognitive function and lower stress?

View full article →

Win a BB Weighted Blanket (valued at $249)
Win a BB Weighted Blanket (valued at $249)

January 01, 2020

Body Benefit Blankets is giving away an amazing BB Weighted Blanket (valued at $249). Enter your name for a chance to win!

Weighted health blankets are known to help improve sleep quality, ease restlessness, and improve concentration. Body Benefit Blankets is giving away an amazing that can be used by anyone in your family.  


View full article →