For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
In 1996, research found that having excessive body hair is linked to higher intelligence.
23
A human being loses an average of 40 to 100 strands of hair a day.
133
Your body is creating and killing about 2.4 million red blood cells per second.
17
The average sperm cell swims at 8 inches per hour.
76
The levels of two stress hormones, cortisol and epinephrine which suppress the body's immune system, will actually drop after a dose of laughter.
112