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
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
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