It takes about 20 seconds for a red blood cell to circle the whole body.
102
Enamel is hardest substance in the human body.
61
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190