Enamel is hardest substance in the human body.
61
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
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
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
Your body is creating and killing about 2.4 million red blood cells per second.
17
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118