Are you getting enough deep sleep at night? Sleep is one of the most powerful forces impacting your health and well-being, yet more than one-third of Americans aren’t getting enough of it. Even if you are reaching the recommended 8 hours of snooze time each evening, you could still be coming up short of one particular type of sleep: deep sleep.

It’s time to take a deep dive into deep sleep, and explore the ways deep sleep benefits your health and how you can get more of it.

What Exactly is Deep Sleep?

When you go to bed at night, your brain traverses from wakefulness through different sleep cycles: deep sleep and REM sleep (or dream sleep).

If you were able to look at your brain waves, the patterns of electrical activity in your brain change dramatically as you move from wakefulness to deep sleep to dreaming sleep.

While awake, your brain waves are rapid and appear surprisingly chaotic. Your waking brain is quickly processing information and stimuli from various parts of your brain simultaneously.

As you fall into sleep, you enter the first phase of sleep, a phase known as non-rapid eye movement (NREM), deep sleep, or deep wave sleep. At this phase, your brain waves slow down significantly. They also sync up into a predictable pattern, moving in a single direction from the frontal lobes toward the back of the brain.

From deep sleep, you transition into the REM sleep phase. During REM (rapid eye movement) sleep, your brain waves pick up speed and become less organized, similar to what your brain waves look like during wakefulness. This is the dream phase of sleep, where your mind is active while your body sleeps.

You will cycle through deep sleep and REM sleep multiple times throughout the night, each phase bringing its own unique benefits (and challenges).