For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
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
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
The human body contains over a billion miles of DNA.
147
Poor eyesight (myopia) is associated with higher IQ.
232
One human hair can support 3 ounces.
191