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Medicine

Why does ice cream sometimes trigger a splitting headache?

Quick fact

Brain freeze is caused by a sudden constriction and then rapid dilation of blood vessels in the palate and sinuses, which activates the trigeminal nerve—the same nerve responsible for facial pain and migraines.

Why this is interesting

Brain freeze—or 'ice cream headache'—is your brain's overreaction to a rapid temperature drop at the roof of your mouth, causing blood vessels in your head to dilate and trigger pain receptors.