What happens in the body during sleep?

Sleep is an important part of the body’s schedule and has been scientifically proven to be necessary. During sleep, the human body is in an economical mode, the brain, heart and other organs are resting, since a person’s metabolism slows down greatly. The muscles relax, the lactic acid accumulated in them from daily activity is absorbed. Brain cells also rest, as they are inactive during this period. Immunity is increased, which contributes to the recovery from viral diseases. Blood circulation slows down.