Why do sneezes come in twos or threes?

Ah choo... don't try to stop a sneeze, you could be doing your nose a snotty disservice.

Asked by: Tom England, Liverpool

Sneezing is a way for your body to reset the nasal environment by getting rid of any irritating particles and restoring the correct level of mucus – either too much mucus or too little can trigger a sneeze. For a single sneeze to guarantee to shift any possible irritant, it would have to be dangerously powerful. Sneezes already expel air at 160km/h (100mph), so it’s safer to just chain a few sneezes together if the first doesn’t do the job.

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