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
It takes about 20 seconds for a red blood cell to circle the whole body.
102
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
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
One human hair can support 3 ounces.
191
When you take a step, you are using up to 200 muscles.
886
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190