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A man biting into an ice cream cone, with a see-through head showing cold spreading across the roof of his mouth and a blue nerve leading to an orange flash of pain in the front of his brain
A man biting into an ice cream cone, with a see-through head showing cold spreading across the roof of his mouth and a blue nerve leading to an orange flash of pain in the front of his brain
Body

What is brain freeze?

Brain freeze is a short headache that happens when something very cold touches the roof of your mouth. Blood vessels there react to the sudden cold, a nerve sends pain signals, and your brain feels the pain in your forehead instead.

1Cold

Something icy hits the roof of your mouth

A big bite of ice cream or a fast gulp of a slushie chills the roof of your mouth in a second or two. Eating or drinking cold things quickly is the classic trigger.

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2Vessels

Blood vessels squeeze, then swell

The sudden cold makes the blood vessels in the roof of your mouth narrow, and then quickly widen again to warm the area. That rapid change is thought to set off the pain.

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3Nerve

A nerve sounds the alarm

A large nerve in your face, the trigeminal nerve, picks up the change and sends pain signals up to your brain. The same nerve also carries feeling from your forehead.

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4Pain

Your brain blames your forehead

Because the signals arrive along a nerve that also serves the forehead, your brain places the pain there. Doctors call this referred pain: you feel it somewhere other than where it starts.

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The answer

A cold mouth, a misplaced headache.

Cold palatenerve signalforehead pain

Brain freeze usually fades within half a minute and is harmless. Your brain isn’t actually getting cold, it just misreads where the signal comes from.

Common follow-up questions

How do I stop brain freeze fast?

Warm the roof of your mouth. Press your tongue or thumb against it, or sip something lukewarm. Then slow down with the cold treat.

Is brain freeze dangerous?

No. It’s a brief, harmless headache that goes away on its own. Frequent headaches that come without cold food are worth mentioning to a doctor.

Why doesn’t everyone get it?

Sensitivity varies a lot between people. Some get it from a single sip, others hardly ever. People who often have migraines seem to get it more.

Can cold drinks cause it too?

Yes. Slushies and iced drinks gulped through a straw are common triggers, because the cold goes straight to the roof of your mouth.

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