A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
The human brain is more active during sleep than during the day.
28
Dieters who sleep more take off more fat that those who sleep less.
159
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
44% of kids watch television before they go to sleep.
106
There's a love mattress that is specifically designed for couples who sleep on each other's arms.
12