Ice cream conundrum

Penn researchers explain what happens when ice cream and other frozen treats cause “brain freeze” and tooth sensitivity.

As summer temperatures skyrocket, people reach for ice-cold drinks and ice cream, some 23 pounds per American per year, according to the International Dairy Foods Association. Along with short-term refreshment, these chilly delights can also cause sharp, shooting mouth pain or the occasional “brain freeze,” although the two reactions are completely unrelated, says neurologist Roderick Spears of Penn Medicine.

“Brain freeze starts with a cold stimulus, such as ice cream, touching the palate, the roof of the mouth,” says Spears, a clinician in the Department of Neurology in the Perelman School of Medicine. The cold temperature causes vasoconstriction, when blood vessels constrict or shrink quickly.

But this isn’t what causes brain freeze. Instead, the pain comes from a rapid warming process called vasodilation, during which the vessels rebound back to regular size to counteract the initial rapid cooling. This signal heads to the brain via the trigeminal nerve. Because the trigeminal nerve is responsible for facial sensation, people often perceive this ice cream–related discomfort in the forehead or face.

“This pain can last for anywhere from a few seconds to a few minutes,” says Spears. “But there’s an easy way to avoid it.” Slow down.

study published in The BMJ (formerly the British Medical Journal) discovered that brain freeze occurs more frequently when people consume ice cream quickly.

Such a solution can’t help someone whose teeth hurt from sensitivity to the cold, explains Panagiota Stathopoulou, a periodontist with Penn Dental Medicine. People with healthy teeth and gums shouldn’t experience tooth sensitivity, she says. If this is happening, it could indicate that something is wrong.

“When someone experiences tooth pain or sensitivity, pain stimuli comes in contact with the tooth either directly or indirectly,” says Stathopoulou, an assistant professor of periodontics and director of the Postdoctoral Periodontics Program.

Read more at the Penn One Health Communications website.