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
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
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
When you take a step, you are using up to 200 muscles.
886
The human body contains over a billion miles of DNA.
147