For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
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 doesn't stop developing until about 25 years old.
102
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
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
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193