One ESSENCE beauty editor spent her holiday in the Equinox Hotel sleep lab—here’s how to deepen your sleep at home this ...

Deep sleep is one of the most essential stages of the sleep cycle, playing a vital role in how well you feel both physically and mentally. Often referred to as slow-wave sleep or delta sleep, this ...

Deep sleep, like all sleep stages, helps you feel refreshed when you wake up. The proportion of time you need to spend in ...

"I have to get my deep REM sleep," expresses a common confusion about two very different types of sleep. Deep sleep and rapid eye movement (REM) sleep are not the same; they do not even overlap. They ...