Warning: Cold weather is a bigger threat to your health than heat

Take these three simple precautions to stay safe and sound this winter

This past June, July, and August were the hottest summer months recorded in the northern hemisphere, according to data from the National Oceanic and Atmospheric Administration.1

So it’s not surprising that we heard a feverish amount of advice from public health authorities about how to protect ourselves as the temperatures rose.

But now, as temperatures drop, is when they really need to issue caution. Because when it comes to our health and safety, it’s actually cold weather that’s responsible for almost all temperature-related deaths.

In a moment, I’ll tell you three simple steps you can take to protect yourself from the hazards of cold weather. But first, let’s take a closer look at how cooler temperatures affect our health…

Deadly cold

A new study by researchers with the University of Illinois at Chicago found that cold temperatures were responsible for 94 percent of temperature-related deaths.

Researchers looked at both inpatient hospitalizations and outpatient visits to hospital urgent care units for temperature-related problems in Illinois between 2011 and 2018.2

They found there was almost an equal amount of cold-related and heat-related cases—23,834 and 24,233, respectively. But there were 1,935 deaths due to cold weather and only 70 deaths related to heat. Notably, people over the age of 65 and Black people were twice as likely to be hospitalized for temperature-related reasons.

People who had heart disease, kidney failure, or dehydration and electrolyte imbalances were also more commonly hospitalized—which may explain why older and Black people were more affected, since they can be more prone to these conditions.

The study also pointed out that Chicago has had a decrease in the number of extreme cold-weather days during the last several decades—but doctors still see far more deaths resulting from cold (rather than hot) weather.

To understand why, it’s helpful to know how the body naturally acclimates to temperature changes…

Natural thermostats

There are many physiological adjustments the body makes to keep its internal temperature at or around 98.6 degrees, even when outside temperatures rise and fall, like an internal thermostat.  (This is called “thermoregulation.”)

These adjustments occur naturally during gradual seasonal shifts, like in the spring and fall. But the body can also make many short-term adjustments when subjected to daily heat and cold cycles, or when simply going outdoors during extreme weather.

Of course, thermoregulation is poorer when people don’t have time to acclimate to the extreme heat or cold. And that’s when problems set in. Plus, people who are regularly exposed to lower temperatures are better able to resist hypothermia.

Hypothermia occurs when the body’s core temperature drops to 95 degrees or lower. People who have hypothermia have trouble naturally thermoregulating—making them more susceptible to temperature-related health issues.

For instance, the Chicago study found that hypothermia due to cold was responsible for 27 percent of hospital visits due to extreme temperatures.

Why hypothermia is so dangerous

As a forensic pathologist serving as an expert witness for maritime law proceedings, I once investigated deaths that had occurred in the ocean—both in northern and southern waters.

I quickly discovered that deaths from exposure, or hypothermia, in the water are more common than drowning. That’s because any body of water that’s colder than the normal human body temperature has the potential of conducting heat away from the body and beginning the progression of hypothermia.

When water temperatures are in the 80s, people can typically continue to generate sufficient body heat to avoid hypothermia. But when temperatures drop into the 60s and 70s, hypothermia begins to set in, and death can occur in as little as four hours.

Your fate only gets worse as temperatures continue to drop—and hypothermia and a loss of consciousness set in more rapidly.

But you don’t even have to get wet for hypothermia to occur. Hospital doctors observe that even mildly cool outside air temperatures can also initiate it.

Interestingly, hypothermia is actually the body’s way of protecting itself from cold—at least for a little while. When a person first experiences hypothermia, his or her blood and energy flow contracts to the core of the body to conserve heat. Then, vital organs and systems begin to shut down in order to maintain the brain.

Unfortunately, once this hypothermia process has begun, it’s difficult to reverse—which is why it’s so deadly.

Sweating out the details

By contrast, heat-related problems are far more likely to resolve by simply getting to a cooler space and drinking water. In fact, as long as the body is hydrated, it has the ability to cool off by sweating.

Sweating also uses the heat-conductive properties of water in reverse. When sweat forms, it takes heat out of the body. Then, the sweat evaporates into the air, turning into a vapor state—a thermodynamic transition that takes a lot of heat energy away from the body.

But it’s important to note that since sweat carries some salts (electrolytes) out of the body, proper hydration means replenishing with water and electrolytes.

Of course, when the air is more humid, evaporation of sweat is less efficient, since the atmosphere is already laden with moisture. That’s why it’s easier to cool down in dryer climates.

My three steps to stay healthy and safe this winter

Even though the process of how cold and heat affects our bodies is complicated, there are some surprisingly simple steps you can take to stay safe and healthy as the temperatures drop…

1.) Stay warm. This is especially important if you live in a climate where it doesn’t get too cold very often. As I mentioned earlier, if you spend most of your time in warm climates, your body doesn’t have as much practice making the adjustments that protect your core temperature, which can make you more susceptible to hypothermia—and even death.

So bundle up when the temperature drops. Protect your core with a jacket or heavy vest. Keep heat from escaping from your head with a warm, close-fitting hat. And protect your vulnerable extremities with gloves, socks, and warm shoes or boots.

2.) Stay dry. Getting drenched by rain or snow doesn’t make you more susceptible to colds. But it does make you more susceptible to hypothermia. So if you do get wet when the temperatures are low, get into a warm room and dry off as soon as you can.

3.) Stay hydrated. This is the step that may seem counterintuitive, since we tend to think more about drinking water when the temperatures rise. But hydration is important no matter what the thermometer reads. And we can often be less aware we’re dehydrated when the weather is cooler.

Plus, both indoor and outdoor air during the winter can actually draw moisture from our bodies.

Heating systems bake the humidity out of indoor air. So when you breathe it in, your lungs get dry—and consequently, transfer moisture from your body. And cold, outdoor air has a reduced ability to hold humidity—creating the same effect.

So make sure to drink plenty of water in winter. Even better, add some powdered rooibos extract to your water. This South African plant helps keep your body hydrated at the cellular level. And, when combined with other botanicals like blueberries and rose hips, rooibos offers even more support.

Bottom line: Don’t fall victim to the cold this winter. Stay warm, dry, and hydrated to protect your health—both inside and outside.



2“Clinical outcomes of temperature related injuries treated in the hospital setting, 2011–2018.” Environmental Research, 2020; 189: 109882.