Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain has the capacity to store everything that you experience.
4k
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Every year your body replaces 98% of your atoms.
119
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
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