Bats sleep 18-20 hours per day.
5
The human brain is more active during sleep than during the day.
28
There's a love mattress that is specifically designed for couples who sleep on each other's arms.
12
You forget 90% of your dreams.
256
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Dieters who sleep more take off more fat that those who sleep less.
159