Your body is creating and killing about 2.4 million red blood cells per second.
17
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
One human hair can support 3 ounces.
191
Yawns are more contagious among people with closer relationships.
163
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
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
Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18