Those who get out of bed by 7am are more likely to be thinner and happier.
20
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Bats sleep 18-20 hours per day.
5
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
People who sleep late have more mental stamina and can outperform early risers.
33
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240