Sleep is a vital part of human life. Some people believe that they aren’t getting enough sleep, while others sleep too much. Our need for sleep changes slightly over time, but sleep is necessary for our brains to stay healthy. Here are 6 other fascinating facts about sleep:

1. 12% of People Dream in Only Black & White. It’s a proven fact that an older generation dreams only in black and white. We are having to go off of the memories that they actively recall, but a resounding 12% of people experience this phenomenon. Scientists believe that it’s influenced by watching black and white tv programming. As the years have gone on, and colored tv has become the standard, this phenomenon has waned.

2. Humans Sleep One Third of Their Life. We need to have about 6-8 hours of sleep per night, depending on our age, activity level, and gender. As we age, we generally sleep a few hours less a night than when we are younger. Interestingly enough, women need more sleep per night than men. If we sleep about 8 hours a night, that’s ⅓ of our day. That means that over a lifetime, we will have slept ⅓ of our entire lives!

3. The Longest Record of Being Awake is 11 Days. You can live longer without food than you can without sleep. You can live approximately 21 days without food, but you can only live 10-11 days without sleep. Your brain begins to shut down, stopping your involuntary bodily functions, like heartbeat, breathing, and digestion. A research student conducted this sleepless study under medical supervisions. Others have died with less sleep. Do not attempt this.

4. 15% of People Sleepwalk: Sleepwalking is a nighttime phenomenon that affects about 15% of the population. Its technical name is somnambulism. Despite the common myth, it’s perfectly fine to wake a person sleepwalking. They will be confused and possibly defend themselves, so wake them up from a distance if possible. Sleepwalkers usually commit harmless tasks such as turning on and off lights, moving objects, or relieving themselves in closets. It’s most common in childhood, and most outgrow it during teenage years.

5. Everyone Dreams 4-7 Times Each Night: Everyone dreams, even if they don’t remember their dreams. During our deep sleep, or REM cycles, our brains create dreams that can seem to last seconds or days.

6. You Dream Of People That You’ve Seen: Our brains do not fabricate new faces during our dreams. We only dream of people that we’ve seen before – even if it was only for a split second. Our minds will pull from memories of people that we know well, old school mates, childhood friends, people on the train, or other past memories.

Our minds are amazing things. Even though sleep may be slightly different from person to person, one thing remains the same – we all need it. Find a good sleep routine and stick to it so you can get the perfect amount rest that you need every night.