Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Enamel is hardest substance in the human body.
61
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The human body contains over a billion miles of DNA.
147
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266