It takes about 20 seconds for a red blood cell to circle the whole body.
102
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
Poor eyesight (myopia) is associated with higher IQ.
232
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
When you take a step, you are using up to 200 muscles.
886