Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human body contains over a billion miles of DNA.
147
Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Every year your body replaces 98% of your atoms.
119
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
When you take a step, you are using up to 200 muscles.
886
The average person's skin weighs twice as much as their brain.
131