If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Enamel is hardest substance in the human body.
61
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
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
The human body contains over a billion miles of DNA.
147
The average sperm cell swims at 8 inches per hour.
76
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18