Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and …

Jun 19, 2023 · Sleep is a body process that allows your body to rest, repair and restore itself. You need sleep to function properly. Lack of sleep has links to many health issues.

Jul 10, 2025 · Everyone needs sleep, but about one in three American adults don’t get enough of it. The consequences of sleep deprivation are serious, so it’s worth learning why sleep matters, how it …

Feb 25, 2025 · Sleep is a complex and dynamic process that affects how you function in ways scientists are now beginning to understand. This webpage describes how your need for sleep is regulated and …

May 15, 2024 · Quality sleep means you are getting uninterrupted and refreshing sleep. Getting quality sleep is not just about how many hours you sleep, but how well you sleep.

Jun 1, 2025 · Sleep affects nearly every part of your health, from brain function to immune strength. Learn what happens in each phase of sleep, how to manage common disruptions, and simple ways …

What exactly does sleep do for your body and mind? Here’s what researchers know about the science of sleep—including the stages of sleep, your biological clock, health connections and more.

Dec 14, 2025 · As we sleep, our brain moves through four stages and two phases: non-rapid eye movement (NREM) and rapid eye movement (REM). The brain has four stages within the NREM …

Jan 31, 2025 · Consider simple tips for better sleep, from setting a sleep schedule to including physical activity in your daily routine. Many factors can interfere with a good night's sleep — from work stress …

Sleep is important for your physical and emotional health and wellbeing. Learn about sleep stages, healthy habits and tips for a better night's rest.