Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Enamel is hardest substance in the human body.
61
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13