Table of Contents
Introduction
Have you ever wondered what helps you sleep at night? Or have you felt an urge to sleep after a long period of being awake? If you have thought of these questions, then yes, you have come to the right spot. In this blog, we will see what makes you sleep? and how, with relatable examples and in the end, you will get some tips.
These two culprits make us sleep and they gonna be in the spotlight here –
- The Circadian rhythm
- Sleep pressure
Before getting into this, we have to know the basic principle for easier understanding.
Basic principle within our body and with the universe
Principle of the universe: We are part of the universe. So, any change that occurs in the universe will also occur in our bodies. Think about it: The entire day light, darkness and temperature keep changing because of the Earth’s rotation. That means our bodies go through the same changes the entire day.
Principle within our body: In-depth, there will be a change in each function of our body, which goes up and down like a see-saw the entire day. But our body maintains a normal range and has a limit level for each function. When a function goes out of normal range, it may be either high or low or if it has reached the limit level, automatically our body will bring that function back to normal range.
Survival of the fittest: So, our body changes and adapts to the environmental changes to maintain a balanced state with the universe and also maintain the balance within our body. Isn’t this wow? How our body does these things.
If we don’t adapt and sync or lose the balance within our body, we will be diseased.
Now that you become familiar with the basic principles, we can move on to the next part on how Circadian rhythm and Sleep pressure make us sleep.What helps you sleep at night
Circadian rhythm
Earth’s dance: Earth’s rotatory dance created a rhythm within the living organisms called Circadian rhythm. Circadian means “approximately a day” and here rhythm means “sync in time or to flow”.
Definition of Circadian rhythm: Circadian rhythm is the natural physical, mental and cell-level changes that occur in our body the entire day, which syncs in time with the environmental changes caused by Earth’s rotation.
In simple words, like hair blowing with the air, Circadian rhythm means to flow with the environmental changes each day.
What helps you sleep at night
Circadian rhythm and sleep
This naturally developed circadian rhythm processes the sleep-wake cycle in our body in response to environmental changes. Let’s see how this natural change makes us sleep.
Messenger: A few hours after sunset, a chemical messenger called Melatonin is produced from the pineal gland which is located at the back of our brain. This messenger announces to our body and brain that it’s time to start the sleep cycle, like an alarm that rings in a company which indicates the shift is over.
Melatonin is only an initiator of the sleep cycle; it won’t be present throughout the cycle. This means taking melatonin pills or having melatonin-rich foods, only prepares your body to sleep, like making the bed.
The vampire: Melatonin is also called the hormone of darkness, which means this hormone is produced only in darkness.
What helps you sleep at night
Melatonin and the modern world: Unfortunately, even after sunset, our world is filled with bright lights, and exposure to them makes your body think it is daytime. So, it delays the onset of melatonin secretion and sleep time changes, which means our rhythm is out of sync with the Earth’s dance. This is one of the reasons why you deal with sleep disorders and other health issues.
Research has shown that other than sunlight, blue light also influences the circadian rhythm, because of Melanopsin. It is a blue light-sensitive protein present in our eyes.
Studies proved using mobile phones and laptops and exposure to bright lights before sleep, delays the onset of melatonin production.What helps you sleep at night
What helps you sleep at night
You may think, then what about the moonlight?
Moonlight does not affect the circadian rhythm and is not as effective as sunlight/blue light.
What helps you sleep at night
Sleep pressure
Adenosine: Our body converts the food we eat into ATP (Adenosine triphosphate) and uses it as a fuel to run the functions. ATP is further broken down to release energy, leading to the release of adenosine. This adenosine is either reused or eliminated as waste from the body.
Adenosine pressure: The longer we are awake, our body uses more energy and produces more adenosine. That means the adenosine level will exceed the normal range, which puts our body under pressure. This pressure caused by the adenosine is called sleep pressure.
Sleep pressure and sleep: As our body is under adenosine pressure, to relieve the pressure it has to bring the adenosine level back to normal, which is not easy until we are awake. So, it has to stop us from being awake and it also needs a break to bring the excess adenosine back to the normal level. So, it makes us sleep.
Why?
Because sleep is the resting period during which our body’s activities are reduced. In simple words, sleep is the opposite of awake, which means we won’t pile up the adenosine anymore.
And our body also gets a break period to do its cleaning activity.
What helps you sleep at night
That’s why you feel the urge to sleep after being awake for a long period. During sleep, the adenosine that is not reused is converted into uric acid and eliminated in urine. By making us sleep, our body brings the adenosine back to the normal level.
Excess adenosine leads to excess uric acid. Excess uric acid deposits in joints and causes joint pains and also forms kidney stones. Getting enough sleep and maintaining a healthy diet keeps adenosine and uric acid levels in a normal range.
What helps you sleep at night
Do circadian rhythm and sleep pressure work together?
Circadian rhythm and sleep pressure are two different factors. They work separately but support each other. No matter how high the sleep pressure, the circadian rhythm continues as usual. That’s why you won’t be satisfied with daytime sleep because that is not the time to sleep as per the rhythm.
As adenosine pressure comes back to normal range during sleep, we are supposed to wake, don’t we? No, because the melatonin will keep on producing until it gets the signal from sunlight to stop its production. Thus, the sleep cycle continues.
During sleep, adenosine pressure reduces but melatonin keeps production until sunlight hits us and that’s why we sleep throughout the night and wake up during the day.
Circadian rhythm starts the sleep cycle and sleep pressure makes us sleep. If we follow the circadian rhythm, it will regulate the proper sleep-wake cycle.
What helps you sleep at night
Summary
Whatever changes in the environment, that change happens in our bodies too. Circadian rhythm is to flow with those changes and sleep pressure is the urge to sleep. So, the circadian rhythm syncs with the environmental changes and prepares our body to sleep at night and sleep pressure makes us sleep. Follow the circadian rhythm properly to get good sleep and to live healthy.What helps you sleep at night.
Tips
- Maintain a healthy circadian rhythm.
- Sleep only when you feel sleep-pressured.
- Keep your room dark. It helps to produce enough melatonin to start your sleep cycle.
- If you can’t keep your room dark, wear a sleep mask.
- Use dim orange/yellow lights after sunset.
- Avoid using mobiles and laptops or exposing yourself to bright lights after sunset for at least 2 – 4 hours before sleep.
- Don’t be exposed to bright light when you wake in the middle of sleep.
- Be physically active to produce enough adenosine, which makes you sleep.
- Don’t skip sleep. The damage you made to your body on weekdays by skipping or not getting enough sleep won’t be repaired if you sleep on the weekend for extra hours.
Reference
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What helps you sleep at night
