Here is Why Sleep is So Important for the Human Body

It’s much more surprising than you think.

Photo from bruce mars on Unsplash

After a long and busy day at work, people just want to go home and collapse on their bed.

Some people skip brushing their teeth.

Some people skip washing their face.

Some people skip setting their alarm for the morning.

Some people skip changing their clothes as soon as they come home.

This is what happens when the urge to sleep becomes too great.

Even though you shouldn’t be skipping on your priorities before sleeping, sleep in itself is necessary for the human body to regenerate, heal, and repair itself so it’s ready for the next day.

According to a study in 2018, 51% of adults worldwide report that on average they get less sleep than they actually need.

Think about that.

More than half of the world does not get enough sleep and the consequences are significant.

The main benefits of sleep are:

It helps you feel energized and ready for the next day.

It boosts and supports the immune system.

It prevents and reduces the risk of many diseases.

It boosts cognition and keeps the brain healthy.

It helps you feel energized and ready for the next day.

During sleep, the body repairs and heals itself in so many ways. The body restores many functions such as temperature regulation, normal hormone levels, etc. during high-quality sleep.

During sleep, the body repairs cells, tissues, and muscles that have sustained damaged throughout the day. The brain flushes out harmful toxins that have accumulated through the day and this in turn keeps the brain healthy.

There is only so much the human body can sustain and handle. Imagine running a huge marathon that took up most of your day and then being told to take a 3-hour test. It would be very difficult to do without first having adequate sleep.

When the body repairs and heals itself during sleep, this preps the body for the challenges of tomorrow. When you are asleep, the sympathetic nervous system relaxes which cause blood pressure, heart rate, and temperature to decrease. Many neurotransmitters such as serotonin and dopamine are regulated during sleep which keeps these hormone levels stable.

All of this has the added effect of relieving the stressors on the body during sleep while boosting the recovery effect on the body.

It boosts and supports the immune system.

There is a reason why sleeping when you are sick helps you feel better and relaxed. Sleep gives the body a chance to repair and build up its defenses against an illness.

When you are awake and moving around, the body’s muscular system, nervous system, cardiovascular system, endocrine system, etc. are in performance mode to help support the body. When you go to sleep, your muscles relax, heart rate & blood pressure goes down, and the whole body is in a calm and relaxed state. This gives the body more time and energy to focus on fighting a pathogen or virus which ultimately helps overcome the illness faster.

T-cells play a very important role in the immune system. There are two types of T-cells: Helper & Cytotoxic. Helper T-cells help and coordinate the immune response against pathogens while Cytotoxic T-cells are the killer cells that directly attack pathogens. Sleep has been shown to improve both T-cell levels in the body and its proper functioning.

When you are asleep, the body has time to scan the entire body for hidden pathogens. Doing so allows the body to locate and destroy these pathogens before they have a chance of causing a disease or illness.

It prevents and reduces the risk of many diseases.

Having enough high-quality sleep is important for the body as a whole. Sleep helps keep the body systems working properly so they can collectively support and protect the body.

Chronic sleep deprivation negatively affects all aspects of the body. It can cause an increased risk of high blood pressure, diabetes, stroke, heart attack, cognitive decline, accidents, etc. The list goes on and on.

Lack of sleep consequences:

  1. A lack of sleep is associated with an increased risk of type 2 diabetes. This is because a lack of enough high-quality sleep negatively influences the way the body manages glucose. With continued loss of sleep, less insulin (hormone that regulates blood sugar) is released into the blood after you eat and this results in a buildup of glucose in the blood which can lead to diabetes.
  2. A lack of sleep contributes to the formation of atherosclerosis which is the buildup of fat and cholesterol along arterial walls. If atherosclerosis is left to progress for too long, then this can cause a lack of blood flow to critical organs such as the heart resulting in a heart attack. A lack of enough sleep also leads to elevated blood pressure throughout the day which can put too much stress on the cardiovascular system.
  3. A lack of sleep increases the risk of weight gain and obesity. Insufficient sleep is known to promote hunger and appetite. This is mainly because people who don’t get enough sleep have increased levels of a hunger hormone called ghrelin and decreased levels of the fullness hormone called leptin. Studies have shown that these people consume around 300 calories more than when they are well-rested.

It boosts cognition and keeps the brain healthy.

Getting enough high-quality sleep on a regular basis helps solidify and preserve memories in the brain. During sleep, the brain sorts through all different kinds of memories and determines which gets to move to long-term storage. Neural connections that form our memories get stronger and become more active during sleep.

Sleep helps us remember stuff that we learned during the day. That’s why its recommended to always get adequate sleep every night especially before a major exam to help ensure the brain consolidates those memories into storage. Pulling all-nighters does not benefit the brain and can result in worse performance on cognitive-based tests.

A lack of sleep results in feeling less productive and efficient the very next day. Chronic sleep deprivation can affect everything from cognition to decision making. During sleep, connections between nerve cells strengthen which improves the overall activity of the brain.

Additionally, our brains grow new neurons during sleep which later connect with existing neurons to grow new neural networks. The brain tries to solve existing problems while you are asleep. For example, if you are having a hard time solving a problem and you go to sleep your brain will keep trying to solve that problem while you are asleep. That is why some people almost abruptly yell out an answer or solution as soon as he/she wakes up. The brain was quietly tackling the problem in the background.

When sleep is shortened or interrupted, cognitive performance takes quite a dip. This sleep deprivation negatively affects attention and decision-making performance.

This shows how important sleep is important to one’s mental & physical health.

Final Thoughts

As you can see, getting adequate high-quality sleep is extremely important. It not only rejuvenates and energizes the body, but also gives the body the much needed energy to support all the body systems.

Not getting enough sleep for long periods of time (chronic sleep deprivation) has such a disastrous effect on the body. This can accelerate aging, affect memory and mood, and lead to cognitive decline.

Everyone should be getting at least 7–8 hours of quality sleep. Note that I used the word: quality.

If you keep waking up when you are asleep, you are not getting quality sleep.

If you sleep in an environment where even the slightest light shines through, you are not getting quality sleep.

If you sleep in an environment that is too cold or too hot, you are not getting quality sleep.

If you sleep in an environment that is naturally noisy, you are not getting quality sleep.

Getting 7–8 hours of sleep in an environment that is dark, quiet, and at an ideal temperature goes a long way in ensuring that your body’s sleep needs are being met.

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