A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
A new parent will lose about 1055.6 hours of sleep in the first year of their child's life - almost 44 days!
6
The human brain is more active during sleep than during the day.
28
The average person falls asleep in seven minutes.
115
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Dieters who sleep more take off more fat that those who sleep less.
159
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34