It takes about 20 seconds for a red blood cell to circle the whole body.
102
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
The human body contains over a billion miles of DNA.
147
The average person's skin weighs twice as much as their brain.
131
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18