The Debunker: Will Sleeping in Extreme Cold Kill You?

by Ken Jennings

 

T. S. Eliot wrote that “April is the cruelest month,” but January brings the Northern Hemisphere its cruelest temperatures of the year. We’ve asked ex-Jeopardy! champ Ken Jennings to come in from the cold and put a chill on some of the most persistent cold-weather myths he could think of. You shall know the truth and the truth shall set you freeze (yes, we stole that from Arnold Schwarzenegger’s dialogue in Batman and Robin.)

Icy Myth #2: Don’t Fall Asleep in the Cold—You Could Die!

Hypothermia kills over six hundred Americans per year, mostly as a result of exposure during cold-weather recreation. One common symptom of late-stage hypothermia is drowsiness, and so we get the common trope in survival narratives—both real and fictional—of the mountain climber or Arctic trekker who just wants to lie down in the snow and rest. No, he is told by his brave companions! If you lie down, you will never wake up!

Remembering that hypothermia can cause you to doze, some outdoorsmen (and outdoorswomen, of course, if that’s a word) worry about falling asleep in survival situations, afraid that the reverse could be true as well: that dozing can cause hypothermia. This doesn’t seem impossible—core body temperature does fall during sleep, after all—but it turns out not to be a problem unless the sleeper is already suffering badly from exposure to the cold. “Unless you’re severely hypothermic,” said Quebec Life Flight nurse Lance Taysom at a 2010 conference on wilderness rescue, “uncontrollable shivering will wake you up before you get too cold. When that happens, run around or do some jumping jacks or something else to warm up before trying to catch another nap.”

Sleeping is difficult in very cold conditions, of course, but experienced survival types know that it’s important to stay rested, since sleep deprivation can lead to fatally poor decision-making in life-or-death situations. Some have speculated that Robert Falcon Scott’s ill-fated South Pole expedition ended in tragedy in part because his men had trouble sleeping due to the bitter cold and the “midnight sun.” So it’s a mistake to avoid sleep in a survival scenario for fear of freezing to death. The earlier stages of hypothermia, like shivering, will wake you up long before your rest becomes your final one.

Quick Quiz: Robert Scott arrived at the South Pole in 1912, only to find that what rival had beaten him there a month previous?

Ken Jennings is the author of Because I Said So!, Brainiac, Ken Jennings's Trivia Almanac, and Maphead. He's also the proud owner of an underwhelming Bag o' Crap. Follow him at ken-jennings.com or on Twitter as @KenJennings.

Photo by Flickr user West Vancouver Archives. Used under a Creative Commons License.