The average person's skin weighs twice as much as their brain.
131
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human body contains over a billion miles of DNA.
147
Your thumb is about the same size as your nose.
124
One human hair can support 3 ounces.
191
Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18