Your thumb is about the same size as your nose.
124
Every year your body replaces 98% of your atoms.
119
The human body contains over a billion miles of DNA.
147
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average person's skin weighs twice as much as their brain.
131
Enamel is hardest substance in the human body.
61
One human hair can support 3 ounces.
191
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13