Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Every year your body replaces 98% of your atoms.
119
Yawns are more contagious among people with closer relationships.
163
The average person's skin weighs twice as much as their brain.
131
The human brain has the capacity to store everything that you experience.
4k
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
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99