For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human brain doesn't stop developing until about 25 years old.
102
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human body contains over a billion miles of DNA.
147
Your body is creating and killing about 2.4 million red blood cells per second.
17
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266