People frequently believe that sleep is merely a time when a weary brain finally gets to rest. But in reality, your brain still functions when you sleep. As you sleep, The brain eliminates waste from the system and heals for everything, from blood vessels to the immune system.Studies suggest the body goes through repair processes most effectively when you sleep. its essential for maintaining your health and well-being over the long term. What occurs when you sleep has an impact on how you feel when you wake up.