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
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Your heart will pump about 212 million liters in its lifetime.
26
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217