Sneezing

[Anima]

actually when a heart skips a beat it means that it [b]does[b] stop working and it actually does, thats why people say "bless you" because you didn't die, if you sneeze a bunch of times it's very dangerous because every sneeze skips a beat

I always thought that people said bless yo because it was a matter of politeness that meant please be well and no ill. The historical view posted by MichaelXY was neat, though.