Your heart does not really skip a beat when you sneeze, but it may pause for a fraction of a second before resuming its normal rhythm, says Dr. Thomas Graboys, a cardiologist at Brigham and Women’s Hospital.
The reason people say “God bless you” when a person sneezes is that people “used to believe that in that slight pause, you were between heaven and hell. If you were blessed, you would be saved from damnation,” Graboys says.
The pause probably occurs due to a change in intra-thoracic pressure, or pressure in the chest, when you sneeze. That pressure change may stimulate the vagus nerve, which in turn slows the heart rate down for a very brief moment.
There is no danger in this slight pause, Graboys says. In fact, he says, what is more interesting is not the medical significance of the pause but “how the fable has evolved over the last five centuries.” The persistence of people’s belief in blessing the sneezer has a lot to do with the fear of the devil, he says.
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