Bats sleep 18-20 hours per day.
5
Those who get out of bed by 7am are more likely to be thinner and happier.
20
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
44% of kids watch television before they go to sleep.
106
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
The human brain is more active during sleep than during the day.
28
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15