Second of a five-part series about low body temperature.

by James Hubbard, M.D., M.P.H.

You’d think a cold, snowy mountain would be the setting for most deaths from low body temperature (hypothermia). But that’s not the case. Most people die in urban areas—many inside. In fact, almost every year there are deaths in Florida—sometimes even Hawaii.

There must be something besides cold weather that can cause a low body temperature.

There is.

First, the air temperature doesn’t have to be freezing. It just has to be cold enough to lower your own 98.6 down a few degrees. Usually that takes an air temperature of less than 50 degrees. But not always.

There are other factors that put you at risk even if the temperature is higher. Below are are a few examples.

1.     Being young or old.

The temperature regulators don’t work as well at the age extremes, even as young as age 65. Also children under age 3 have more skin surface versus body mass—more skin to take away the heat.

In addition, the cold has a tendency to slip up on these age groups before anyone notices.

2.    Alcohol and Drugs.

They dull your senses (especially if you pass out, to point out the obvious). Alcohol also dilates up those surface veins I wrote about in the last post, making your skin all warm and flush but at the expense of less heat for your vital organs.

3.    Getting wet.

Water conducts heat 30 times more rapidly than air. That means you get cold a lot quicker and at higher temperatures than when dry. Deaths occur annually in boating accidents and the like. That explains most of the deaths in Florida and Hawaii. Your body temperature can get dangerously low in any water below about 91 degrees F. Of course, the colder the water, the faster it happens.

Get out of those wet clothes. And before going out,dress in layers. That lets the air circulate more, and you can take off a layer before you start sweating if you get too warm.

4.    Chronic diseases.

Hypothyroidism, Parkinson’s, heart disease, and severe infections are examples of many problems that affect your body’s heat regulation. People with these issues can’t fight off the cold as well.

5.   Trauma victims.

If you’re treating a trauma victim, remember to cover the victim with a blanket or whatever’s available. Get the person out of wet clothes also. Trauma can wreak havoc with body-temperature regulators. Also the victim might not notice how cold he or she is getting due to pain or an impaired mental status.

If you’ve had hands-on experience with hypothermia or have any questions, please comment.

The next post will be on symptoms–when to suspect the body temperature is getting dangerously low. In the post after that, I will go into hypothermia treatment.


Five-Part Hypothermia Series:

  1. Low body temperature: How cold is too cold?
  2. (This post) Risk factors for hypothermia (besides cold weather)
  3. Symptoms of hypothermia
  4. Hypothermia treatment, part one: How to treat a conscious person
  5. Hypothermia treatment, part two: How to treat an unconscious person