Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you take a step, you are using up to 200 muscles.
886
Yawns are more contagious among people with closer relationships.
163
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Your heart will pump about 212 million liters in its lifetime.
26
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118