Everyone knows that it is impossible not to sleep. Shortage of 7-8 hours of sleep per week causes burning pain and itching of eyes, chill, fits of weakness and drowse, depression.

The first symptom is loss of humor. A human desires no entertainment. Some people feel personal inutility, guilt of impossibility to keep up with common rhythm of life. Another extreme of this state is aggressiveness and rudeness to people around.

Deficit of sleep influences power of apprehension. Scientists found out that loss of 4 hours of sleep per night slows down human reaction by 45%. If person doesn`t get enough sleep his abilities of attention concentration, logical thinking and retention worsen.

A sleep is a part of protective function of organism. When we sleep speed of metabolic processes reduces saving energy and resources for struggle against microbes.

Desire for sleep is not a symptom of laziness. One should satisfy needs for sleep completely. If you sleep less than 8 hours per day then you don`t have a good night rest and always drowse during the day. To keep healthy psychological balance, person must sleep 9-10 hours per day. Sleep can last continuously for whole night or can be separated on night and day one. When people were given opportunity to sleep as much as they want, they spent this amount of time for sleep.

Full-value rest will save a human from many misfortunes, improve efficiency of work, mental state and mood. And if you are in good spirits you will not make mistakes, which may cost a life.
sections: Nature & Health