Why does spicy food make my nose run?

Asked by: Smera Ahuja, Winchester

Spicy compounds are produced by plants to deter animals from eating them. They have evolved to be as irritating as possible to the mucous membranes of mammals. In fact, the capsaicin in chilli doesn’t actually cause tissue damage, but it triggers the nerve receptors that normally detect heat, and your nose is fooled into producing extra mucus to protect your sinuses.

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