Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Your body is creating and killing about 2.4 million red blood cells per second.
17
Poor eyesight (myopia) is associated with higher IQ.
232
One human hair can support 3 ounces.
191
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
If you are cold you are more likely to be hungry because you use energy to keep warm.
143