For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The average sperm cell swims at 8 inches per hour.
76
The average person's skin weighs twice as much as their brain.
131
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Your body is creating and killing about 2.4 million red blood cells per second.
17
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Poor eyesight (myopia) is associated with higher IQ.
232