How humans handle cold, avoid frostbite

The clothes we wear protect us from the cold, but when we do expose our body, it goes into auto pilot.

Warming up can take almost an hour, according to one health unit

(Submitted by Kati Panasiuk)

Although experts have disputed the 'feels like' wind chill as a factor, Northern Canadians have said it applies when you're outside naked.

Kevin Milne, associate professor of human kinetics at the University of Windsor said the clothes we wear protect us from the cold, but when we do expose our body, it goes into auto pilot.

"If we expose our body to cold, one of the first thing that happens is we move blood into the core, your midsection," said Milne. "The body does that automatically."

In cold situations, the body moves blood from the extremities to the core, which is why your fingers, toes and ears get cold.

If you (or your ancestors) have lived in cold climates, Milne says the body starts to adapt.

"There is some evidence to suggest that people who have long ties to cold environments, they do something different than you and I would," said Milne. "They would move blood away from the fingers and then after about five to ten minutes they move blood back to the fingers, for a re-warming."

(Submitted by Arlene Kochaniec)

You've probably noticed when you're cold, you start to shiver. That's a defence mechanism your body has.

"If you stimulate your muscles to contract and relax, you generate a fair amount of heat," said Milne, comparing shivering to exercising. 

Milne said it's important to wear a hat and gloves to protect your extremities from extreme cold temperatures, adding that fingers aren't "important organs" which is why the body abandons them to warm up everything else.

According to Milne, it's important to evaluate the conditions outside when deciding what to wear and where to go.

Look outside," said Milne. "If there's freezing rain, if it's windy, those increase the risk factor for yourself."

The Windsor Essex County Health Unit said everyone is at risk from the cold, but the elderly and the young are especially at danger. 

Symptoms of frostbite:

  • shivering
  • confusion
  • uncoordinated movements
  • area of skin turning red, blue or grey/white
  • pain, numbness and stiffness in extremities

Milne also said to watch for feelings of numbness as a sign of when things are going wrong.

"You're getting a formation of ice crystals inside your cells. When you're frostbitten, nothing is moving," said Milne, adding that warming up is when you'll know you've caused damaged.

"As soon as you start to warm up, an important consideration is not to put your hand over a candle or a stove. You can do much more damage that way."

The Chatham-Kent Public Health Unit advises to gently warm potentially frostbitten skin in warm, not hot water. The health unit said re-warming may take up to an hour.

Tips from health units on preventing cold-related injuries:

  • dress warmly, cover as much exposed skin as possible
  • wear a hat (30 per cent of body heat escapes through the head)
  • stay dry — remove layers to avoid sweating
  • keep moving, especially hands and feet
  • seek shelter or limit time spent outside
  • drink warm fluids and avoid alcohol
  • check on neighbours


To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.