When you take a step, you are using up to 200 muscles.
886
Your body is creating and killing about 2.4 million red blood cells per second.
17
Your thumb is about the same size as your nose.
124
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
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
The average person's skin weighs twice as much as their brain.
131
Every year your body replaces 98% of your atoms.
119
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197