Your thumb is about the same size as your nose.
124
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Every year your body replaces 98% of your atoms.
119
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Chewing gum boosts your brain power.
285
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22