We talked to sleep doctors about the tell-tale signs of not getting enough deep sleep and what to do about it. What is deep sleep? There are two primary sleep phases: rapid eye movement (REM) and ...

Deep sleep refers to slow-wave sleep — a stage in the sleep cycle when brain waves slow down. Getting enough deep sleep is crucial for numerous bodily functions. But how to increase deep sleep isn’t ...

Here’s why sufficient sleep matters, how much you really need and some evidence-based support for better rest.