Yawns are more contagious among people with closer relationships.
163
Your heart will pump about 212 million liters in its lifetime.
26
The average sperm cell swims at 8 inches per hour.
76
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain doesn't stop developing until about 25 years old.
102
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Poor eyesight (myopia) is associated with higher IQ.
232
The human body contains over a billion miles of DNA.
147