What Happens to You While You Sleep?

Is there anything better than crawling into bed after a long day or taking a nap after tackling housework? There are few things greater than getting some much-needed sleep.

Catching ZZZs is an essential—if not the most essential—part of maintaining your health. In fact, sleeping is so important to our well-being that we spend about one-third of our lives doing it.

But what makes sleep so necessary and important? Regardless of how much sleep you need or how much you get—though it’s probably safe to say we all could use more quality rest—the answers are all about what happens within your body while you sleep.

Related: Why Sleep Is Important for Weight Loss

Though it doesn’t seem likely, your brain and body are actually quite active while your consciousness is off playing in dream land. Sleep occurs in two patterns throughout the night: Rapid Eye Movement (REM) and Non-rapid Eye Movement (NREM).

NREM sleep

When you first begin falling asleep, you enter N1 sleep. The light rest your body experiences in N1 sleep only lasts for about seven minutes. During this first stage of sleep, your body’s muscles relax while your breathing, heartbeat, and brain waves slow down. It’s easy to be woken up during N1 sleep.

Following N1 is N2 sleep. This stage is a continuation of the body’s functions and brain waves slowing down. If you take a quick cat nap, you’d want to wake up during this stage before you enter deeper sleep.

Your body then enters N3—the stage where your body experiences deeper sleep. If you’ve ever had a hard time waking up, there’s a good chance you were in N3 sleep.

Interestingly, N3 sleep occurs in longer periods during the first half of the night. Your heartbeat, breathing, and blood pressure reach their lowest levels of activity during N3. This stage is when tissue growth and repair happens, energy is restored, and various hormones are released.

REM sleep

REM sleep follows N3 stage of sleep. This stage of sleep generally occurs after the first 90 minutes after you’ve fallen asleep and will recur about every 90 minutes throughout the night. During REM sleep, your eyes begin moving—you guessed it—rapidly. Most of our dreams take place during REM sleep.

REM sleep is the best stage of sleep for your body. This stage of sleep provides energy to the brain and body, and it plays an important role in learning and memory function. During REM sleep, your brain consolidates, processes, and stores the day’s information into its long-term memory.

Sleep helps restore and refresh your body and mind. Getting quality sleep helps you function and respond better to various situations throughout your day, too.

Related: Why Sleep Is Important at Any Age

So, whether your mind is busy dreaming of fairytale lands or running late for an exam (or simply a blend of who-knows-what), just know your body and brain are working hard to ensure you’re performing at your best.


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