Black Teeth?

Today we're always trying to make our teeth whiter! 
 
Did you know once upon a time people were trying to make their teeth blacker? 
 
Believe it or not, in ancient Japan when you had black teeth it was a sign of beauty and status. They placed a little bit of vinegar and a little bit of iron filings on their teeth and it made them black. They called it “ohaguro”, so look it up!