Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Your thumb is about the same size as your nose.
124
Yawns are more contagious among people with closer relationships.
163
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
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