Yawns are more contagious among people with closer relationships.
163
Every year your body replaces 98% of your atoms.
119
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Chewing gum boosts your brain power.
285
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
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22