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
Every year your body replaces 98% of your atoms.
119
Yawns are more contagious among people with closer relationships.
163
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Your heart will pump about 212 million liters in its lifetime.
26
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22