Everyone needs time to regenerate. The sleep gives such opportunities. The length of sleep affects the well-being, mood, and health. Many people think that a small amount of sleep per week, when getting up from work, you can catch up on the weekend, sleeping even more than ten hours. However, this is not true. Mental and physical health depends on regular sleep, which should last about eight hours. Too short and too long sleep did not affect well on the body. You feel tired, depressed, lacking in energy. Sleeping three, four hours in the future may lead to insomnia and other diseases.