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
Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
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
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
When you take a step, you are using up to 200 muscles.
886