The average person's skin weighs twice as much as their brain.
131
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Yawns are more contagious among people with closer relationships.
163
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18