The human brain is more active during sleep than during the day.
28
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
Dieters who sleep more take off more fat that those who sleep less.
159
Sleeping on the job is acceptable in Japan. It is viewed as exhaustion from working hard. Some people fake it to look committed to their job.
57
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240