The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
The human brain doesn't stop developing until about 25 years old.
102
Your heart will pump about 212 million liters in its lifetime.
26
The average person's skin weighs twice as much as their brain.
131
In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
199
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217