Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The average sperm cell swims at 8 inches per hour.
76
The human brain doesn't stop developing until about 25 years old.
102
Every year your body replaces 98% of your atoms.
119