12 Health Mysteries Explained

Why yawning is contagious, what causes hiccups, and other miscellaneous body trivia.

What Is Brain Freeze?

It’s a pain in your head that occurs when the nerves on the roof of your mouth are hyperstimulated by cold foods, like ice cream and frozen drinks. The nerves are in your mouth, but the nerve center is in your brain, “so that’s where you feel the pain,” says Seymour Diamond, M.D., a headache specialist in Chicago and the executive chairperson of the National Headache Foundation. “This is known as referred pain.” Why do humans experience pain in one place when the stimulus is elsewhere? No one knows for sure. “We do know that migraine sufferers are more prone to ice cream headaches,” Diamond says. “We also know that eating slowly and sipping slowly seem to reduce the effects of the cold. Once the headache sets in, the fastest way to make it go away is to drink something lukewarm.”