That's just an old wives' taleor an urban myth.It's like saying God Bless You when you sneeze as folklore says the devil can steal your soul when you rmouth is open when you sneeze.It's like the poem we have over here Sneeze on Monday, you sneeze for danger.Sneeze on Tuesday,kiss a stranger.
I heard that when you sneeze its because someone is talking about you
I hear that if you sneeze 3 times in a row something bad will happen... Hope that's not true BUT I also heard if you tell a fib your nose will grow (I watched Pinocchio and my mom said it would happen to me like it did to the puppet that my nose would grow if I lied) so... Lol funny thing is when I use to tell a lie which was really rare I would put my hand on nose to keep it from growing. :)