For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
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
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
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
Your thumb is about the same size as your nose.
124
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
One human hair can support 3 ounces.
191