Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Poor eyesight (myopia) is associated with higher IQ.
232
When you take a step, you are using up to 200 muscles.
886
Yawns are more contagious among people with closer relationships.
163
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The largest cell in the human body is the female egg and the smallest is the male sperm.
682