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
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Poor eyesight (myopia) is associated with higher IQ.
232
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
One human hair can support 3 ounces.
191
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
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