Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
Every year your body replaces 98% of your atoms.
119
The human body contains over a billion miles of DNA.
147
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
When you take a step, you are using up to 200 muscles.
886
If you are cold you are more likely to be hungry because you use energy to keep warm.
143