Your thumb is about the same size as your nose.
124
Yawns are more contagious among people with closer relationships.
163
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Every year your body replaces 98% of your atoms.
119
Your body is creating and killing about 2.4 million red blood cells per second.
17
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
When you take a step, you are using up to 200 muscles.
886
It takes about 20 seconds for a red blood cell to circle the whole body.
102