Yawns are more contagious among people with closer relationships.
163
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
When you take a step, you are using up to 200 muscles.
886
The human brain uses approximately as much energy as a 10 watt light bulb.
120
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