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 adult human brain weighs about 3 pounds (1,300-1,400 g).
99
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
When you take a step, you are using up to 200 muscles.
886
One human hair can support 3 ounces.
191