Poor eyesight (myopia) is associated with higher IQ.
232
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Yawns are more contagious among people with closer relationships.
163