For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
When you take a step, you are using up to 200 muscles.
886
The average sperm cell swims at 8 inches per hour.
76
The human body contains over a billion miles of DNA.
147
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Enamel is hardest substance in the human body.
61