Enamel is hardest substance in the human body.
61
Only humans shed emotional tears.
331
In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
198
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
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
Crying literally alleviates stress and uniquely allows humans to decrease feelings of anger and sadness.
24
One human hair can support 3 ounces.
191
The average person will go on a date at least 100 times before they finally marry.
33