Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human body contains over a billion miles of DNA.
147
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
Your thumb is about the same size as your nose.
124