We humans have been stuck with these strange bags of water that we call bodies for the entirety of our existence. 

So it is not surprising that we have spent centuries trying to figure out how they work and break down. 

This curiosity has led us to believe some strange things about our bodies and the things that make them sick. 

This video by SciShow explores five things that humans got really wrong about our bodies. 

Let me know which of these five things you think is the strangest in the comments below!