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
When you take a step, you are using up to 200 muscles.
886
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
The average person's skin weighs twice as much as their brain.
131
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The human body contains over a billion miles of DNA.
147