The average sperm cell swims at 8 inches per hour.
76
Poor eyesight (myopia) is associated with higher IQ.
232
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217