Why does Rudolph have a red nose?

Rudolph the Red-nosed Reindeer is a beloved Christmas story that first appeared in a 1939 booklet by Robert L. May. It truly entered the popular culture canon in 1949 with the song version first performed by Gene Autry, and most of us simply can’t live a Christmas without the 1964 stop-motion CBS television special adaptation.

Rudolph is bullied by his peers for having a bright red nose, but it’s this unique attribute that helps him land a gig with Santa Clause.

This Christmas scientists have uncovered an explanation for Rudolph’s red schnoz. They still haven’t figured out how Santa flies around the world to every house on Christmas Eve, but you’ve got to take holiday magic one step at a time.

Real life reindeers have 25% more capillaries in their nose than humans, and according to John Cullen, PhD, of the University of Rochester in New York, “In colder climates and also when they are higher up in the atmosphere pulling Santa’s sleigh, the increase in blood flow in the nose will help keep the [nose’s] surface warm.”

Can Ince, PhD, of Erasmus Medical Center in Rotterdam, the Netherlands, elaborates:

“These results highlight the intrinsic physiological properties of Rudolph’s legendary luminous red nose, which help to protect it from freezing during sleigh rides and to regulate the temperature of the reindeer’s brain, factors essential for flying reindeer pulling Santa Claus’ sleigh under extreme temperatures.”

So, in essence, Rudolph’s nose is bright red BECAUSE he’s in the front of Santa’s sleigh. Maybe Rudy already had a redder than average nose, which made him get picked on, and then when he leads the sleigh it really shines bright.

The study to look into the reindeer nasal capillaries involved putting the reindeer on treadmills, and they found the reindeers did, indeed, have red noses when they exerted themselves. The humans in the study were given about 100 mg of cocaine which is “is routinely used as a local anesthetic and vasoconstrictor by ear, nose, and throat specialists,” according to the study’s authors.