Enamel is hardest substance in the human body.
61
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Every year your body replaces 98% of your atoms.
119
Your body is creating and killing about 2.4 million red blood cells per second.
17
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
One human hair can support 3 ounces.
191