Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average person's skin weighs twice as much as their brain.
131
Your heart will pump about 212 million liters in its lifetime.
26
The average sperm cell swims at 8 inches per hour.
76
Yawns are more contagious among people with closer relationships.
163
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266