A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Cows can sleep standing up, but they can only dream lying down.
745
The human brain is more active during sleep than during the day.
28
If you hold farts in during the day, they'll just come out when you sleep.
16
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
You burn more calories sleeping than you do watching television.
348
The average person falls asleep in seven minutes.
115