Why do people say 'Bless you', when you sneeze?

Have heard a lot of reasons. Here are a few of my favorite ones -

1. When you sneeze, you heart temporally stops. . . It's an insignificant amount of time that your heart stops, but most consider when your heart stops that you've temporarily died. Therefore, it is polite to "Bless" someone when they have died.

2. Out of compassion for the sneezer and to wish him / her not to be infected with any illness

3. The phrase is used when someone sneezes, since in many cultures it is believed that the soul leaves the body during a sneeze, and God is called on to protect the sneezer from evil spirits at such a vulnerable time.

4. A sneeze is one of the devil's many evil deeds. His goal is to make us sneeze and spread disease or to sneeze while our neck is turned so we break our heads off. I've broken 2 ribs sneezing before. So yea, GOD BLESS YOU the devil is poking you!!

5. There is also a theory that during the Dark and Middle Ages, a violent sneeze was often a precursor of dreaded diseases such as the plague. Whenever someone sneezed, those closest to him or her issued an immediate "Bless you" to ward off the evil forces which led to disease and suffering.