Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The average person's skin weighs twice as much as their brain.
131
Enamel is hardest substance in the human body.
61
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102