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
Your thumb is about the same size as your nose.
124
Enamel is hardest substance in the human body.
61
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Every year your body replaces 98% of your atoms.
119
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 Right Lungs takes more air than our left lung.
194