Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Yawns are more contagious among people with closer relationships.
163
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
Poor eyesight (myopia) is associated with higher IQ.
232
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
Your body is creating and killing about 2.4 million red blood cells per second.
17