Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Your thumb is about the same size as your nose.
124
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62