Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Lack of water is the #1 trigger of daytime fatigue.
148
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
You burn more calories sleeping than you do watching television.
348