Follow us on Google News (click on ☆)
Sleep is not just a break—it's an essential activity for the body and brain. At night, our body takes advantage of this time to repair cells, replenish energy reserves, and strengthen the immune system. It's as if our body enters a maintenance workshop to restore all its parts.
But it's in our brain that sleep plays an even more crucial role. While we sleep, the memories of the day are sorted, categorized, and stored in our long-term memory. Some neural connections strengthen, while others weaken. This process helps us learn, solve problems, and be more creative.
Sleep consists of cycles alternating between different phases. Deep slow-wave sleep, where the body regenerates, and REM sleep, where brain activity almost resembles wakefulness and where our most vivid dreams occur. Each cycle lasts about 90 minutes and repeats several times a night.
Not getting enough sleep has immediate effects: reduced concentration, mood disturbances, and a weakened immune system. In the long term, chronic sleep deprivation increases the risk of cardiovascular diseases, diabetes, and even mental disorders. That's why scientists generally recommend 7 to 9 hours of sleep per night for adults, and much more for children and teenagers.
The reasons for our need for sleep are also tied to our evolution. Biological rhythms, synchronized with the day-night cycle, influence our body temperature, hormones, and alertness. Sleep allows us to conserve energy during times when it's less efficient to seek food or act: at night, for diurnal species like us.
In reality, sleeping is as vital as eating or breathing. It's a time when the body and mind work together behind the scenes so we can be in top shape upon waking.