Your thumb is about the same size as your nose.
124
Every year your body replaces 98% of your atoms.
119
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
One human hair can support 3 ounces.
191
Poor eyesight (myopia) is associated with higher IQ.
232
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190