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Why do we make the 'atchoo' sound when we sneeze? © Getty Images

Why do we make the 'atchoo' sound when we sneeze?

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Instead of 'achoo-ing' Polish people 'apsik', the Japanese 'hakushon' and Germans 'hatschi!'.

Asked by: Mohammad Rashid, Wakefield


A sneeze begins with a sudden inhalation. This is the ‘Aaah’ part of the sneeze. The ‘Choo!’ occurs on the exhale because most of the muscles in your body are reflexively contracting. This clamps your mouth shut until the pressure in your lungs rises too high and the air escapes in a burst. Since your tongue is pressing against the roof of your mouth, the air makes a ‘ch’ sound, and with your lips pursed, it emerges as an ‘oo’.


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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.


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