Sleep is super important, why do we need it every night?

Sleep is really important. It is not only a "resting place" for the body and mind, but also the key to our rejuvenation and health. Have you ever wondered why we need it every night? What makes sleep so indispensable? Let's read today's science story and explore the mysteries behind sleep!

"Kaikai, it's so late, why aren't you sleeping yet?" Mom looked at Kaikai who was still reading in bed.

"Mom, I'm not sleepy. I'll take a rest tomorrow. It's okay to stay up a little later!" Kaikai looked up at his mother and said.

"You can't say that! You need to get enough sleep, especially when you are still growing." Mom laughed, "And if you don't sleep, your brain and your immune system won't be able to complete their work at night."

"Are the brain and immune system divided into day shift and night shift?" Kaikai asked in surprise.

"Although the brain is working all the time and does not rest when we sleep, there is a difference between morning and night. Current research by scientists shows that during sleep, the brain can recharge cells, clean up waste produced by cells, repair information that was not remembered clearly during the day, and lock important information." Mom nodded.

"Wow, no way, it's so magical?" Kaikai asked in disbelief.

"Yes! Cerebrospinal fluid can supply certain nutrients to brain cells and transport metabolic waste from brain tissue to prevent the flow of information between neurons from being affected." Mom smiled, "Many studies have shown that when we sleep, the brain processes the information obtained during the day. The brain will sort out recently formed memories, consolidate, copy, and integrate information. Because we are asleep, the brain will not be disturbed by other information and can recall more effectively. And some experiments have shown that sleep not only strengthens memory, but also screens and selectively retains memories."

"What kind of experiment is it?" Kaikai asked curiously.

"Scientists asked subjects to look at a set of pictures, some of which made people feel unpleasant, while others were neutral. When the subjects fell asleep, they found that they remembered the pictures that aroused emotions deeply, while they forgot the others." The mother explained, "In short, when we sleep, the brain helps us organize and store the memories and information we have generated during the day, and cleans up the waste produced by the brain. In this way, we can be refreshed the next day!"

"Then what does the immune system do at night?" Kaikai frowned and said, "I don't think the immune system works at night!"

"Why do you say that?" Mom asked with a smile.

"For example, if I'm sick, I feel my condition gets worse at night. It's obvious that my immune system is slacking off!" Kaikai explained.

"A study in 2019 found that the immune system has day and night. Generally speaking, the daytime work focuses on attacking bacteria and viruses, while the night is mainly responsible for repairing and removing old cells. It no longer attacks bacteria and viruses vigorously, so the symptoms naturally feel more serious." The mother replied, "But night is the time for repair. If you don't remove old cells and clean up the viruses and bacteria that were killed by the immune system during the day, and let the immune system repair itself after working all day, how can it continue to work the next day?"

"It seems that these 'workers' in the body really start work and rest on time!" Kaikai laughed.

"Yes! And putting aside these studies, if we don't sleep for a long time, it will lead to endocrine disorders, and we may have adverse reactions such as constipation or weight gain. And over time, our tempers will become uncontrollable, not only manic, but some people will also have hallucinations. The whole brain is dizzy." Mom said, "So, sleeping is actually more like a physiological need of ours. The energy is consumed during the day, and we need to rest and recharge at night, right?"

"Mom is right. I'm going to sleep now, good night!" After saying that, Kaikai crawled into the bed and closed his eyes.

【Knowledge Card】Can people live without sleep?

Although the brain is always working and does not rest when we sleep, there is a difference between morning and night. Current research by scientists shows that during sleep, the brain can recharge cells, clean up waste produced by cells, and process information obtained during the day: sort out recently formed memories, consolidate, copy, integrate, filter and retain information. The immune system is also affected by the biological clock and there is a difference between day and night.

Long periods of sleep deprivation can lead to endocrine disorders, which may cause adverse reactions such as constipation or weight gain. The temper will also become uncontrollable, and some people will not only be manic, but also have hallucinations, and the whole brain will be dizzy. Sleeping is actually more like a physiological need of ours: we consume our energy during the day, and we need to rest and recharge at night.