She says when we eat spicy foods, something called our trigeminal nerve is actually irritated.

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Triptans, which promote blood-vessel constriction and inflammation, block the release of CGRP in the trigeminal nerve.

WSJ: Fresh Target in Hunt for a Migraine Cure

The reason may be that capsaicin excites the trigeminal nerve, increasing the body's receptiveness to the flavour of other foods.

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Experts disagree about how a migraine is triggered, but the trigeminal nerve—an important pathway that carries sensory information about the face—and its connections to numerous other nerves and the brain appear to be responsible for transmitting the pain.

WSJ: Fresh Target in Hunt for a Migraine Cure