freeze

Brain Freeze

The short headache triggered by cold food and/or drinks touching the inside of your mouth.

To start, brain freeze (aka “ice cream headache” or “cold-stimulus headache”) only affects about 30-50% of the population. Most people can eat ice cream and drink extra cold drinks without any fear of reprisal from their nervous system.

Brain freeze occurs when the roof of your mouth or the back of your throat suddenly come into contact with cold food, cold drinks, or even cold air. The trigeminal nerve in your head reacts to the cold by telling the arteries connected to the meninges (the membranes surrounding your brain) to contract to conserve warmth (much like how our bodies react to the cold in general). Then the body sends more warm blood up to the head telling those same arteries to expand. This quick succession of vasoconstriction and vasodilation of blood vessels triggers pain receptors along the trigeminal nerve which creates the pain you feel behind the eyes or forehead during a brain freeze.

A lot of nerve

While we all have a trigeminal nerve its varying sensitivity may explain why not everyone gets brain freeze. For example 37% of Americans may get brain freeze but only around 15% of Danish adults do. Further, 93% of people who get migraines are also susceptible to brain freeze.

Winter Warmer

Drinking alcohol in cold weather only warms you temporarily and then you need to get inside.

Our bodies are designed to regulate heat in order to stay alive. When you’re too hot the blood vessels nearest the skin use vasodilation to open wide and allow heated blood to pass through and radiate heat away from the body, cooling you down.

When you’re cold you body does the opposite. In the cold your body uses vasoconstriction to close off the blood vessels closest to the skin to prevent heat loss. In order to keep your core warm your body limits the blood flow to your extremities, conserving heat. This is why your fingers, toes, skin, etc. get stiff & cold before your core. Fingers are expendable, your organs are not. When your body is using vasoconstriction to keep warm the last thing you want to do is dilate those blood vessels … which is exactly what alcohol does.

From old myths and advertisements, the idea that alcohol is a good way to warm up in the cold has been around for centuries.

Hot Shots

Part of why we think alcohol helps comes from St. Bernards rescuing avalanche victims in the snow wearing small barrels of brandy to warm them up. Unfortunately no St. Bernard dog has ever worn such a cask – it’s a myth popularized by the Edwin Landseer 1820 painting Alpine Mastiffs Reanimating a Distressed Traveller.

Probably the main reason we think alcohol warms us up in the cold is because it sort of does. Alcohol is a vasodilator and so it isn’t the alcohol warming you but what alcohol does to the body that warms you. In the cold alcohol opens the blood vessels that the body has closed down to preserve warmth, the result of which is that the warm reserve of blood in your core is suddenly released out to your extremities. Unfortunately this sudden warmth comes at a cost. As the warm blood reaches your extremities there is a loss of heat and as it travels back to your core your overall body temperature drops. Further, alcohol reduces your body’s ability to shiver (which is another mechanism used to increase warmth) so you’re cold and only getting colder. Now you no longer have a reserve of warmth and need to get indoors.

In this bootlegged video from MythBusters, they explore the myth that alcohol helps warm you up in cold weather.