If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Yawns are more contagious among people with closer relationships.
163
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
The human body contains over a billion miles of DNA.
147
Your thumb is about the same size as your nose.
124
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515