Yawns are more contagious among people with closer relationships.
163
Every year your body replaces 98% of your atoms.
119
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Enamel is hardest substance in the human body.
61
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Chewing gum boosts your brain power.
285
Your heart will pump about 212 million liters in its lifetime.
26
The human body contains over a billion miles of DNA.
147