What Causes Brain Freeze?

July 9, 2020 - Katie McCallum

Sphenopalatine ganglioneuralgia: You've probably never heard the term, but there's a good chance you've experienced the phenomenon.

It's hot outside, you're sweating, the snow cone in your hand is delightfully cold. You take a big bite, only to regret it immediately. A sharp pain begins radiating through your brain and every part of your face clenches. You squeeze your eyes together. You squint your nose upwards. You pinch the skin on your forehead together. And, just as quickly as the pain comes, it goes.

You've just experienced "brain freeze" — that throbbing pain you feel in your forehead or temples after drinking or eating something way too cold, way too quickly. But why does shocking your mouth with something cold cause pain in your forehead? And is there anything you can do to prevent it?

Why do brain freezes happen?

While the pain typically only lasts a short while (a few seconds to less than five minutes), brain freeze is classified as a type of headache, believe it or not, according to the NIH.

More colloquially called an "ice-cream headache," this occurs when the roof of your mouth goes from its usual, warm temperature to one that's much, much colder — when you're drinking a slushie or biting into a snow cone, for instance.

In an effort to hold onto what heat is left, blood vessels in the area constrict and then relax. This rapidly increases blood flow, which, in turn, initiates signals of pain.

Why do you ultimately feel the pain in your forehead and not the roof of your mouth? Theories abound, but the most prominent of these involve one of the most complex nerves in your brain, the trigeminal nerve. The thought is that brain freeze triggers this nerve, which (among other things) controls sensation, including pain, in your face. A phenomenon called "referred pain" occurs, causing you to feel the effects of brain freeze in your forehead and temples instead of your mouth.

Estimates suggest that around 40% of people are susceptible to brain freeze. While researchers don't yet understand why, it may indicate that the trigeminal nerve is more sensitive in some people than in others. The NIH says that migraine sufferers are more susceptible to brain freeze.

How to stop brain freeze

Unlike other types of headaches, which last longer and usually require medication or other remedies, treating a brain freeze is as easy as warming your mouth back up. In addition, while painful, a brain freeze is actually harmless and isn't anything to alert your doctor about.

As far as how to deal with brain freeze, your best bet is to try to prevent it altogether by eating cold foods slowly, taking small sips or bites. It's hard to resist slurping a slushie or biting into a popsicle as soon as it's in your hands, though.

If you feel a brain freeze coming on, you might try the following: