It takes about 20 seconds for a red blood cell to circle the whole body.
102
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average person's skin weighs twice as much as their brain.
131
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
If your DNA was stretched out it would reach to the moon 6,000 times.
256
Enamel is hardest substance in the human body.
61
Poor eyesight (myopia) is associated with higher IQ.
232
If you are cold you are more likely to be hungry because you use energy to keep warm.
143