Your thumb is about the same size as your nose.
124
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
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
The human brain uses approximately as much energy as a 10 watt light bulb.
120
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515