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3. Brain Freeze: Why Can Ice Cream Knock Us Out?

Brain freeze, also called an ice cream headache, can strike with the very first bite of ice cream or sip of a cold drink. This quick but intense sensation offers a fascinating glimpse into just how sensitive the brain is to cold.

It’s an experience many of us have had, often while sitting at a café terrace in summer or sharing a bowl of ice cream with friends. You take a bite, swallow too quickly, and suddenly a sharp pain shoots across your forehead, a jolt so sudden it makes you stop in your tracks. The term “brain freeze” captures this almost absurd sensation, as if the brain itself were freezing. Yet this very real phenomenon has intrigued scientists for decades.

So, what is really happening in your head during a brain freeze? Despite the sensation, your brain is not actually freezing. It all starts in the mouth, specifically at the roof of the mouth. When you eat or drink something very cold too quickly, the palate, rich in blood vessels and nerve endings, experiences a sudden temperature shock. This causes the blood vessels to narrow and then quickly widen again in a reflex response. While this reaction helps protect the tissues and restore normal temperature, it also activates pain-sensitive nerves, mainly the trigeminal nerve, which provides sensation to the face.

The brain picks up an alert that something extremely cold has hit the mouth. But through a curious process called referred pain, it can misinterpret the signal, making it feel as if the pain is coming from the forehead or skull instead. That is why biting into an ice cube or gulping a cold drink can send a sharp, intense pain right behind the eyes.

A Neurological Puzzle that Sheds Light on Migraines

Researchers have studied this seemingly harmless phenomenon and discovered that it is more complex than it appears. Brain freeze shares several features with migraines. Recent studies using imaging techniques such as transcranial Doppler have shown that during a brain freeze, a key artery in the brain, the anterior cerebral artery, quickly experiences a surge in blood flow followed by a rapid drop. This sudden rush of blood and the vessel’s quick contraction line up perfectly with the onset of pain. Some neurologists believe this reaction is protective: when the brain is exposed to cold, it increases blood flow to warm itself as quickly as possible. Once the blood flow returns to normal, the pain disappears just as suddenly as it began.

Another interesting observation is that people who suffer from migraines seem more prone to brain freeze. This may be because their nervous system, particularly the trigeminal nerve, is more sensitive to sudden changes, whether caused by temperature or blood flow. Brain freeze is also more common among children, likely because they often eat or drink very quickly and have thinner, more sensitive palates.

Fortunately, the pain is very brief. It usually appears 10 to 30 seconds after consuming something cold and lasts one to two minutes at most. A few simple tricks can help shorten the episode: warming the roof of the mouth with your tongue or thumb, sipping room-temperature water, or simply waiting it out. The best way to prevent brain freeze is to enjoy ice cream and cold drinks more slowly, avoiding a sudden temperature shock.

While brain freeze is harmless, it offers a small glimpse into the subtle connections between our brain, nerves and blood vessels. Beyond this playful reflex, researchers hope to better understand certain types of migraines and perhaps one day develop new treatments. In the meantime, the next time a sorbet sends a chill across your forehead, remember that it is not your brain freezing, but an incredible interplay of nerves and blood vessels. A little patience or a sip of lukewarm water is all it takes to get back to enjoying summer.