Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The human brain doesn't stop developing until about 25 years old.
102
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Yawns are more contagious among people with closer relationships.
163
Our Right Lungs takes more air than our left lung.
194
Every year your body replaces 98% of your atoms.
119