Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you take a step, you are using up to 200 muscles.
886
Enamel is hardest substance in the human body.
61
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human body contains over a billion miles of DNA.
147
One human hair can support 3 ounces.
191
Your thumb is about the same size as your nose.
124
The largest cell in the human body is the female egg and the smallest is the male sperm.
682