What is a brain freeze?
Has this ever happened to you? You’re eating a delicious ice cream cone or frozen lemonade, so cold and sweet and suddenly, bam, brain freeze! What happened?
A brain freeze is a short, intense pain behind the forehead and temples that occurs after eating something cold too fast. If you get one, don’t worry – your brain isn’t actually freezing. The sensation feels like it’s happening inside your skull, but it really has to do with what’s going on in your mouth.
Brain freeze isn’t as common as you might expect. Many studies report that less than half of their participants get them. Scientists still don’t understand why.
What makes a brain freeze hurt?
There’s a lot we know about how a brain freeze works. There’s also a lot we don’t know.
Just beneath the skin on your face is a network of blood vessels that supply the face and brain with blood. Blood contains many nutrients like oxygen, which is essential for your brain to function. Tangled up in this network of vessels are tiny nerve endings connected to one another and the brain through the trigeminal nerve. This nerve makes it possible for you to feel sensations in your face, including pain.
Scientists believe the blood vessels in the throat and mouth and the trigeminal nerve are central to what makes a brain freeze hurt. But they don’t quite agree on which is more responsible for causing the pain.
Most agree that eating or drinking something cold, too quickly, rapidly lowers the temperature at the back of your throat and roof of your mouth. Many also agree this causes the tiny blood vessels in these areas to shrink, allowing less blood to pass through them. This reduces their ability to supply your brain with necessary oxygen in the blood. What happens next is a little blurry.
Pain in the brain means stop!
Some scientists believe the trigeminal nerve responds to these events in your throat and mouth by sending a pain signal to the front of your brain. Whether the nerve is specifically responding to the cold or a sudden reduction of blood and oxygen supply to the brain – or both – is unclear.
Other scientists believe the pain is caused by a rush of blood to the front of your head. Shortly after the vessels in your throat and mouth shrink from the cold, these same vessels immediately expand. By expanding, additional blood and oxygen flood these areas. Although this blood rush might provide your brain with desperately needed blood and oxygen, it also might increase the amount of pressure in your head, causing pain.
Is a brain freeze dangerous?
A brain freeze may seem like a bad thing at first, but the pain could actually be good. By forcing you to stop eating that delicious but cold treat, the pain from a brain freeze may protect your brain from losing its continuous supply of blood and oxygen.
If you’re worried about a brain freeze, try slowing down. It may be hard with something as delicious as a Bomb Pop on a hot summer day, but at least it will last longer.
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Tyler Daniel Anderson-Sieg does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.