Yawns are more contagious among people with closer relationships.
163
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
When you take a step, you are using up to 200 muscles.
886
Your thumb is about the same size as your nose.
124
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human body contains over a billion miles of DNA.
147
Your body is creating and killing about 2.4 million red blood cells per second.
17