Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain doesn't stop developing until about 25 years old.
102
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
The average person's skin weighs twice as much as their brain.
131
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
Every year your body replaces 98% of your atoms.
119
The human body contains over a billion miles of DNA.
147