Enamel is hardest substance in the human body.
61
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
It takes about 20 seconds for a red blood cell to circle the whole body.
102
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
One human hair can support 3 ounces.
191