Question: why does ice cream cause a headache? 

Answer: Most people have experienced the dreaded ice cream headache at some point. You are minding your own business on a hot summer day, eating something like an ice cream cone, a milk shake, a Slurpee, a snow cone... Then, suddenly you are hit with the most excruciating headache! Fortunately it only lasts about 30 seconds. \n\nSo where does this headache come from? \n\nI have not seen a better answer to the question than in this article by Joseph Hulihan. It's a little technical, but it contains some great information. Here's a summary: When something cold touches the roof of your mouth on a hot day, it triggers a cold headache. The cause is a dilation of blood vessels in the head. The dilation may be caused by a nerve center located above the roof of your mouth -- when this nerve center gets cold, it seems to over-react and tries to heat your brain. \n\nTherefore, the easy way to avoid "brain freeze" is to keep cold things away from the roof of your mouth!
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