For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Your body is creating and killing about 2.4 million red blood cells per second.
17
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
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