For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Your heart will pump about 212 million liters in its lifetime.
26
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Your thumb is about the same size as your nose.
124
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197