If you hold farts in during the day, they'll just come out when you sleep.
16
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
17
One human hair can support 3 ounces.
191
There's 100 trillion good bacteria living in your body.
17
Your heart will pump about 212 million liters in its lifetime.
26