Alexandra Pope, staff writer
January 17, 2011 — Five minutes of exposure is all it takes for hypothermia to set in.
It can take as little as five minutes for hypothermia to set in when the human body is exposed to cold, so it's important to take steps to protect yourself before venturing outside during the winter, experts say.
Wayde Lansing, a paramedic with Toronto Emergency Medical Services, said depending on the outside temperature and a person's age and physical fitness, it can take as little as three to five minutes for the body to lose precious heat and begin showing the early symptoms of hypothermia.
“As time increases, and the exposure to the outdoors is maintained over that time, your body's ability to protect itself will decrease, so it'll start switching off systems,” he said.
Small children and the elderly are especially vulnerable to the cold, said Dr. Grant Lum of Athletic Edge Sports Medicine in Toronto.
“Seniors are at risk because they've got a lower body fat content; they've also generally got a bit of dehydration, so consequently they're not able to fend off the cold as easily,” he said.
“That also goes for small children and babies. Because of their smaller size, they're just not able to cope with that changing temperature as easily.”
The key to preventing hypothermia is to limit the amount of time you're exposed to the cold and dress appropriately for conditions. That means dressing in layers, covering your hands, ears and other extremities, and wearing proper footwear to prevent falls when walking in snow and ice.
Lansing said even if you're only planning on being gone for a few minutes, it's important to dress warmly.
“(A lot of people) think, 'Oh, I'm just going to the corner store, I'm going to get in my car and drive' and they have a leather jacket on. Well, what happens if you get in an accident or the vehicle breaks down? You're going to expose yourself potentially to an environment that's hostile to you.”