Enamel is hardest substance in the human body.
61
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Every year your body replaces 98% of your atoms.
119
Yawns are more contagious among people with closer relationships.
163
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
The human brain has the capacity to store everything that you experience.
4k
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118