The human brain doesn't stop developing until about 25 years old.
102
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
One human hair can support 3 ounces.
191
Every year your body replaces 98% of your atoms.
119
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Your body is creating and killing about 2.4 million red blood cells per second.
17
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217