“Wear this jacket or else you’ll get sick!”

It’s a line we’ve all heard from our mothers growing up. We’ve repeatedly been told that staying out in the cold will make us sick. And what about that friend who’s always absent at school whenever the seasons change? You might’ve brushed it off, thinking, “Oh, they must be sick because of the cold weather.” 

After all, it’s common knowledge that being in the cold makes you sick... right?

Well, not exactly. It’s easy to assume that something as simple as the temperature is the reason behind our colds– especially when we’ve grown up with our parents constantly warning us about it. But the truth is, this idea is a myth! In reality, the cold air and wind don’t directly make you sick, although they can increase your chances of catching something in a few indirect ways.

Let’s start with the most important fact. The only way you can get sick, whether it’s from a cold or the flu, is if a virus or bacteria enters your body. That’s right! Chilly weather doesn’t magically create viruses or help them enter your body. 

However, cold weather does make it easier for viruses to spread. Why? Because viruses tend to survive longer in cold, dry air. Plus, when it’s cold outside, people tend to spend more time indoors, often in spaces with poor ventilation. This makes it easier for viruses to circulate and infect others. So, ironically, it’s not being out in the cold that causes sickness; it’s staying inside with others trying to avoid the cold that actually increases your risk.

Now, you might’ve also heard that shivering or being cold makes you “weaker” and more vulnerable to getting sick. That’s another exaggeration. While it’s true that breathing cold, dry air can slightly dry out your nasal passages, making it a bit easier for viruses to enter, and that blood vessels in your nose may narrow in the cold, these effects are quite minor. Your immune system doesn’t suddenly fail just because you forgot your jacket!

Another reason people tend to get sick more often in the winter has less to do with the temperature and more to do with how we live during cold weather. When it’s chilly, we tend to become more sluggish and lazy: moving less, exercising less, and eating more of our comfort foods. These lifestyle changes can make our immune systems a bit weaker. On top of that, there’s less sunlight during winter, which lowers vitamin D levels, and shorter daylight hours can affect our sleep, both of which reduce our body’s resilience. 

To summarize, while cold air doesn’t directly cause sickness, it does create conditions that make it easier to get sick. So the next time someone says, “Put on a jacket or you’ll catch a cold,” you can just smile knowing that the weather is not the real culprit.