10 reasons why sleep is so important.

Scientists increasingly mention sleep as an essential component of a healthy life, along with a varied diet and physical activity. Modern people begin to appreciate the value of night regeneration only when we start to lack sleep - we sleep less and worse than our ancestors ¹ . The reason may be ubiquitous stress and the 24/7 use of digital devices (but not only that). Sleep is as important to our body as breathing , with the difference that we feel the lack of air immediately, and the lack of sleep has side effects in the longer term. Here are the reasons why sleep is strategic for our health.

1. Sleep strengthens your immunity.

Scientists have discovered that during a night's rest, the work of some elements of our immune system speeds up. For example, there is increased production of inflammation-related cytokines ² . In this way , the body fights infections at night and repairs damage, heals wounds, etc. A good night's sleep also increases the immunity acquired through vaccination ^{3, 4} . Regardless of whether a person is sick at a given moment, night regeneration improves his immunological memory.

2. Sleep helps maintain a healthy body weight.

Too little sleep is one of the key factors in the development of obesity. Scientific research shows that people who get little sleep tend to gain weight ⁵ . This applies to both adults and children ⁶ . When we lack sleep, the hormones responsible for the feeling of hunger and satiety (leptin and ghrelin) do not function properly7 ^. After a sleepless night, we also have less strength and motivation to move.

3. Sleep regulates blood sugar levels.

During the deep sleep phase, the amount of glucose molecules in the blood and insulin levels decrease. This time is necessary for the body to reset its insulin sensitivity mechanism. Even if a healthy person sleeps only 4 hours instead of 8 for 6 nights in a row, his or her body can become pre-diabetic ⁸ . People who sleep less than 6 hours every day are at increased risk of developing type 2 diabetes ^{9, 10} .

4. Sleep strengthens the heart.

Lack of sleep or not enough sleep causes the body to secrete more of the stress hormone cortisol. This hormone increases the heart rate. The longer it is secreted, the longer our heart does additional work. During sleep, our heart rate slows down, our blood pressure drops, and our blood vessels have the opportunity to rest a little ¹¹ . By playing (or working) at night instead of sleeping, we strain the heart and increase the risk of a heart attack ¹² .

5. Sleep improves memory and concentration.

Getting enough sleep is important for many brain functions. When we sleep, new neural connections are formed. The brain processes all the information we come into contact with during the day. It is also a time to clean up the toxins accumulated in the brain ¹³ . Lack of sleep, we start to have problems with memory and learning, we start making decisions with greater difficulty ¹⁴ . Just one sleepless night is enough to cause problems with concentrating ¹⁵ . American researchers also claim that drivers who sleep less than 8 hours a night are twice as likely to have car accidents16 ^. They have poorer concentration on the road.

6. Sleep improves athletic performance.

Every athlete knows how important regeneration is, especially at night. Even if you're not a professional, sleep can significantly impact your performance, especially if you train in endurance sports. Lack of sleep deprives you of energy and motivation, and, quite simply, time to rebuild your muscles . It also increases reaction time. However, well-rested athletes consistently show better sports results ¹⁷ .

7. Sleep helps build relationships with people.

It's not just that, sleep-deprived, we don't have the humor or strength to maintain a conversation with others. Researchers have discovered ¹⁸ that sleep deprivation literally changes our brain. It weakens the activity of neurons in those areas that are responsible for involvement in social life. Sleep-deprived people are more hostile towards strangers and less willing to get to know them. If you want to ruin your relationship with your surroundings, just don't get enough sleep on a regular basis.

8. Sleep ensures good sex.

Contrary to appearances, sex does not have to be mutually exclusive with sleeping. Getting enough sleep has a huge impact on libido and the level of sex hormones, and also on fertility and the quality of sexual life, say scientists. For young men aged ^19, 1 week of insufficient sleep (5 hours a day) is enough for their testosterone levels to drop by 10-15%! In women, sleep regulates desire. Studies have shown that each additional hour of sleep at night increases the level of sexual arousal by 14% ^.

9. Poor sleep quality is associated with depression.

Mental illnesses are closely related to sleep disorders. 90% of people suffering from depression also report problems with sleep ²¹ . In turn, people with sleep disorders who have not yet been diagnosed with depression have a greater risk of developing it ²² . The relationship is two-way and for now, scientists cannot say which came first - sleep problems or mental disorders.

10. Sleep fights stress and improves your mood.

American scientists have calculated that to feel happier, you simply need to sleep 60-90 minutes longer at night ²³ . It is the most universal medicine, improving physical and mental health, as well as emotional state. It gives a lot of pleasure and has no side effects, but despite this it is regularly neglected by modern man. And the less we sleep, the higher our stress level ²⁴ . Lack of sleep is itself a stressor, it leads to the secretion of the above-mentioned hormone cortisol, which in excess overloads our body's strength.

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