Every year your body replaces 98% of your atoms.
119
Yawns are more contagious among people with closer relationships.
163
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Your body is creating and killing about 2.4 million red blood cells per second.
17
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