Sleep is a fundamental need for all human beings, especially if they want to be healthy. Sleep is a source of energy. When a person sleeps, all the cells of the liver and flesh are renewed, the immune system increases, the memory becomes stronger and better, and the hormones needed for the body's growth are stable. Full sleep for adults is seven to eight hours. Not only adults suffer from insomnia, but children too. Possible causes: difficulty or too late falling asleep, waking up frequently during the night, waking up too early... Reasons: messy sleeping area, too much light, noise, food that is difficult to digest...