We've all done this, eat or drink something and our head hurts. For a long time I thought it was because I did it too fast. Now, new research gives us the real answer.

In a breakthrough sure to thrill Slurpee lovers everywhere, researchers say they’ve figured out what causes brain freeze.The sharp pain associated with eating cold food like ice cream and other frozen treats appears to be triggered by a sudden change in the flow of blood in the brain’s anterior cerebral artery. The pain comes on when blood flow increases, and subsides as soon as the artery constricts.

via Chilling discovery - The Daily.