47% of people have a nightmare at least once a month.
186
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
People who sleep late have more mental stamina and can outperform early risers.
33
You forget 90% of your dreams.
256
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23