When you take a step, you are using up to 200 muscles.
886
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
It takes about 20 seconds for a red blood cell to circle the whole body.
102
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Our Right Lungs takes more air than our left lung.
194
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18