7 Interesting Things that Your Body Does in Deep Sleep

· June 14, 2016
Contrary to what you might think, when you’re asleep, your body doesn’t just turn off. Do you know what happens during those hours? It might surprise you!

One of the main things your body needs is at least eight hours of sleep every day. While you’re in a deep sleep, your body repairs itself and renews its energy levels to take on a new day with the best physical and mental outlook.

What not many people know, however, is that some interesting things take place when you’re asleep. These things can affect your overall health and quality of life.

If you’ve been thinking that your body essentially shuts off all its processes while you rest, you’re wrong. Although you might not always be aware of it, your body is synchronized with its function and is busy performing some pretty unusual tasks.

In today’s article, we want to reveal all the things that happen when you fall into deep sleep. No doubt you’ll be surprised!

1. Eye movement increases

person with eyes closed, in a deep sleep

We go through about five stages during a sleep cycle, the fifth one being the deepest level of sleep.

It’s known as the REM phase, or Rapid Eye Movement, and is characterized by the continuous movement of the eyes from front to back. You won’t remember this when you wake up.

You usually reach this stage of sleep in about 90 minutes and it makes up almost 20% of your total sleep in the night. For now, no one can explain this phenomenon, but it’s believed to be due to the excitement of the neurons.

See also: Relaxing Infusions That Will Help You Sleep

2. You produce growth hormone

One of the reasons why getting good deep sleep at night is so important is because it’s when your body secretes hormones like human growth hormone. These hormones are needed to regenerate tissues, bones, and muscles. 

In addition, they are essential for the proper development of children. Likewise, the human growth hormone is also required to fight low blood sugar levels and regulate your metabolism.

3. Your kidneys slow down and you burn calories

During the day, your kidneys work hard to filter toxins from your bloodstream and produce urine.

During the night, their efforts slow down and you produce less urine than you would during the day. That explains why you might not need to get up to go to the bathroom at night. Likewise, in the morning, you may notice your urine is darker than usual.

On a similar note, did you know that you also burn calories when you sleep? All the activity that goes on during this period of deep sleep represents a significant expenditure of energy that helps control your body weight.

This is one of the reasons why people who don’t get good sleep tend to have more problems with being overweight or obese.

4. You grind your teeth

person with a mouth guard because they grind their teeth at night

This less-common occurrence could be caused by stress or because your teeth are not properly aligned.

Dental professionals refer to this as bruxism, which can sometimes cause jaw pain and other complications.

It’s important that you see a dentist because this could be a factor that influences long-term processes, such as tooth decay.

5. Sudden movements

This has happened to most people: you’re just falling asleep when suddenly you jump or feel a strong jolt out of bed.

This happens normally and shouldn’t be a cause of concern. What’s going on is that your brain is preparing itself for the shift in sleep cycles and sometimes it gets misinterpreted as a fall.

The phenomenon is technically known as a hypnotic pulse, and it only happens when you’re sleeping.

6. The brain discards what it doesn’t need when in deep sleep

Your brain builds up a lot of information throughout the day and at night it prepares to get rid of what it doesn’t need.

This is your body’s natural way of cleansing the central nervous system. It also serves to discard extracellular proteins, excess fluid, waste products from the metabolic process, and any peripheral tissue.

We recommend you read: 4 Psychological Benefits of Walking

7. Sleep paralysis

sleep paralysis

Almost everyone will experience sleep paralysis at some point in their lives. Some people may experience this more than others. It occurs when you are in the deepest phase of your sleep cycle and is characterized by a nagging sense of immobility while being aware that you’re dreaming.

It can be a very frightening occurrence because it’s often accompanied by nightmares in which you’re unable to escape or react in any other way.

Dao, L. N., Lippe, B., & Laird, M. (2013). Human growth hormone. In Pharmaceutical Biotechnology: Fundamentals and Applications, Fourth Edition. https://doi.org/10.1007/978-1-4614-6486-0_14

García-tornel, S. (1979). Bruxism. British Journal of Anaesthesia. https://doi.org/10.1093/bja/51.8.805-b

McCarley, R. W. (2007). Neurobiology of REM and NREM sleep. Sleep Medicine. https://doi.org/10.1016/j.sleep.2007.03.005

Pelayo, R. (2014). Sleep Paralysis. In Encyclopedia of the Neurological Sciences. https://doi.org/10.1016/B978-0-12-385157-4.00573-X