Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
If your DNA was stretched out it would reach to the moon 6,000 times.
256
Your body is creating and killing about 2.4 million red blood cells per second.
17
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
When you take a step, you are using up to 200 muscles.
886
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18