Why do we need sleep?

Why do we need sleep?

Sleep is very important and we need plenty of it. There are basically two factors that make us feel sleepy. The first one is light when we see lights in the morning our brain releases more amount of cortisol that keeps us awake while when there is dark our brain releases more amount of melatonin which makes us feel sleepy. The second reason why we feel sleepy is adenosine when our brain performs daily activities adenosine gets produced and makes us feel dizzy or sleepy. While sleeping we use very less energy but also conserve our energy more, sleeping reorganizes information and clear out unwanted memories.

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 Tom is feeling sleepy. Can you remember this famous scene from the Tom & Jerry show? What a pitiful situation.  This often happens with us. Your exam is knocking at the door; you have to cover your syllabus. You have your book open in front of you, but you have read only a paragraph in the last half an hour. And you cannot keep your eyes open. It is such a miserable situation

Most commonly when we stay awake for long time or for some reason could not sleep at night, we feel sleepy and tired. Work pressure or pressure of study also makes us feel sleepy. After days of hard work, when we become exhausted, then also, we feel sleepy. But why does this happen?

Everybody knows sleep is very essential for a healthy body and mind. But there is no satisfactory scientific explanation of this question of why we need sleep. Till now, scientists could not find out any cause behind the sleepiness.

Have you ever heard the term internal clock of our body? What is this internal clock? Normally we do certain activity at certain time. We take meals at a specific time; we stay active in particular time period. Also we take rest or we go to sleep in a particular time. This pattern or routine is fixed by nature. How has this daily natural routine been fixed? Our bodies release some chemicals in a 24 hour cycle. These Chemicals regulate our daily activities and encourage or stimulate us to do certain activities at a certain time. Among these chemicals, one of the most important chemical is known as Melatonin. This particular chemical or hormone plays an important role in regulating our sleep pattern. The amount of this hormone in our body increases in the evening and at mid-night its amount becomes maximum. Usually we go to bed at night and are deeply asleep by mid-night. Again, its amount starts to decrease in the morning and allows us or prompts us to wake up from sleep. But remember, this hormone has many other functions in our body too.

There is a small pinecone-shaped gland inside our brain. Its name is pineal gland. Our sleep regulating hormone melatonin is produced by this pineal gland.

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Pineal gland has various functions. One of the most important functions is to regulate our sleep or sleep pattern. Scientific studies have revealed that the Pineal gland in our brain secretes the melatonin hormone. We have already mentioned that the melatonin hormone is stimulated by darkness. In fact the process of regulating sleep starts in the retina that is present in our eyes. When our retina is exposed to sunlight, then a signal is relayed to the pineal gland and it prevents the gland from producing the melatonin hormone. That is why during the day we feel less sleepy and we stay active, do our work in the day time. But when it is night time and there is no sunlight  then no such signals are there for pineal gland. So the pineal gland becomes active and starts producing melatonin hormone. And this hormone tells us to go to sleep and we feel sleepy. Again in the morning sunlight illuminates the surroundings and secretion of melatonin decreases. That is why we wake up in the morning. As the activity of pineal gland is activated by light, it sometimes called the third eye.

Human beings spend about one third of their life span asleep. Without sleep people will fall sick. Experiments have shown that without sleep a rat will die within two or three weeks. Obviously, this experiment cannot be done on human.

We can explain why we eat. We eat when we feel hungry, we eat to live, and we eat to get nutrition. There are many answers for the question of why we eat. But why do we sleep? Till now scientists don’t have any satisfactory answer. It is sure that sleep made us feel better. After a good night’s sleep we feel fresh, energetic and happier. We get energy for work and we become more active after waking up from a good sleep. Without sleep we feel bad, unhealthy, dull and sleepy.

Scientific researches show that sleep does not mean shut down from the world. Rather many activities go on during sleep. Scientists have made many hypotheses on why we need to sleep. Anyway there are many benefits of a good night sleep. Following are some of them:

  • When you are in stress due to pressure of study, or for work pressure, then a deep and uninterrupted sleep may help you to reduce stress.
  • Researches have shown that when you are asleep, your body is getting rest. But your brain is busy in organising and storing memories. So a good quality sleep may help you to remember and to improve your memory.
  • Sometimes sleep is prescribed as a cure for many illness or diseases. When we sleep then our bodies produce extra protein molecules. This extra protein gives us strength to fight infections and other illnesses.
  • A good sleep reduces the chance of many diseases like diabetes, stroke or heart attack. A quality sleep also keeps your heart healthy and keeps your blood pressure under control.
  • Many studies have shown that sleep acts as pain killer. Plenty of sleep may reduce your pain quickly and may make you feel reasonably well.
  • I think, we have all experienced a good mood and a feeling of wellness after a deep and quality sleep.

We have seen that children who are in their developing stage need more sleep than adults.   A one year old baby needs roughly 11 to 14 hours of sleep, a school going child needs 9 to 11 hours of sleep and a teenager needs 8 to 10 hours of sleep. Childhood is that stage of life when people learn many things very fast and it is also their developing stage. So a good night’s sleep is very important in this stage of life.

According to sleep experts ‘If you sleep better, you can certainly live better. It’s pretty clear’.

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