47% of people have a nightmare at least once a month.
186
If you hold farts in during the day, they'll just come out when you sleep.
16
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Those who get out of bed by 7am are more likely to be thinner and happier.
20