Why Do We Get Brain Freezes?

What causes brain freeze? When your body senses sudden, extreme cold in the mouth or throat, it tries to react and warm up. Blood vessels throughout the head expand to let extra blood into the area for warmth. That quick change in blood vessel size causes sudden pain.

Are brain freezes harmful?

"Brain freezes are not dangerous and very self-limiting," Vertrees said. "It's about slowing down and being patient and aware of the likelihood of getting a brain freeze if you eat or drink too fast," she said.

Why are brain freezes so painful?

It's thought that the pain of brain freeze is caused by the triggering of the trigeminal nerve – this nerve carries sensory information from your face and around your head to your brain. Once activated, the blood vessels constrict from the cooling.