Yawns are more contagious among people with closer relationships.
163
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
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
Your body is creating and killing about 2.4 million red blood cells per second.
17
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266