Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Yawns are more contagious among people with closer relationships.
163
Every year your body replaces 98% of your atoms.
119
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
When you take a step, you are using up to 200 muscles.
886