It takes about 20 seconds for a red blood cell to circle the whole body.
102
Your thumb is about the same size as your nose.
124
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Enamel is hardest substance in the human body.
61
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
The average sperm cell swims at 8 inches per hour.
76
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
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217