Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
19
If you hold farts in during the day, they'll just come out when you sleep.
16
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 human brain doesn't stop developing until about 25 years old.
102
