Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
19
Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
You see your nose at all times, your brain just chooses to ignore it.
30
The levels of two stress hormones, cortisol and epinephrine which suppress the body's immune system, will actually drop after a dose of laughter.
112
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
The human sigh acts as a physiological reset button.
23
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22