Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
When you take a step, you are using up to 200 muscles.
886
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Your heart will pump about 212 million liters in its lifetime.
26
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266