The average person's skin weighs twice as much as their brain.
131
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
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
One human hair can support 3 ounces.
191
Enamel is hardest substance in the human body.
61
The human body contains over a billion miles of DNA.
147
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127