Your body is creating and killing about 2.4 million red blood cells per second.
17
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
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