What Happens to Your Lungs in the Cold?

Even in cold, frigid temperatures, your lungs will not freeze or be damaged because your body naturally warms and moistens the air before it reaches the lungs. That said, the cold air can irritate the airways that carry air to your lungs, potentially causing symptoms like shortness of breath or cough.

Can the Cold Harm My Lungs?

Your lungs are not at risk of being damaged or “frostbitten” in cold temperatures.

The reason is that by the time inhaled air reaches your lungs, your body has already humidified (moistened) and warmed it to your core temperature, around 37 C or 98 F.

That said, the processes your body uses to warm and moisten the air before it reaches the lungs can naturally irritate the lining of the bronchi. This irritation causes the muscles within the bronchi to tighten and narrow—a phenomenon known as bronchospasm.

How Inhaled Air Reaches the Lungs

It’s important to understand how the air you breathe reaches your lungs:

• The lungs are encased within the chest cavity, a space surrounded by the upper and middle spine bones, ribs, breastbone, and diaphragm—a dome-shaped muscle that sits below the lungs and heart.
• The diaphragm contracts (tightens) and moves downwards when you breathe in, allowing the lungs to expand.
• The diaphragm’s movement also creates a vacuum that sucks air in through the mouth and nose, down the windpipe (trachea), into two large tubes (the bronchi), and into the lungs.
• The bronchi branch into smaller airways that end in millions of tiny sacs (alveoli) within the lungs.
• The alveoli take in oxygen from inhaled air and exchange it for carbon dioxide, a waste gas that is exhaled.

What Are the Symptoms of Bronchospasm?

Potential symptoms of bronchospasm include:

• Coughing
• Wheezing (a tight, whistling sound when breathing)
• Burning or tight sensation in the chest when inhaling
• Feeling short of breath
• Unusual tiredness or exhaustion (less common)

In severe cases, bronchospasm can significantly obstruct the airways, leading to a drop in oxygen levels. Symptoms of low oxygen levels may include dizziness, feeling faint, drowsiness, or developing a bluish tint on the fingers, toes, or lips.

Who Is More Prone to Bronchospasm in the Cold?

Bronchospasm from bitterly cold temperatures can occur in individuals with healthy lungs.

However, those with underlying lung diseases, namely asthma and chronic obstructive pulmonary disease (COPD), are at higher risk because their airways are more vulnerable to inflammation or are already inflamed at baseline:

• In asthma, inflammation affects the larger airways, leading to reversible airway swelling and narrowing. Baseline lung function is normal in individuals with asthma.
• In COPD, inflammation affects the smaller airways, making them swell and narrow. Excess mucus is also produced, which can clog the airways. The alveoli in lung tissue can also be damaged in COPD. Baseline lung function in individuals with COPD is abnormal.

In lung diseases like asthma or COPD, which can also overlap, the cold, dry air can trigger bronchospasm, which could lead to an asthma or COPD exacerbation/flare-up. Such exacerbations, if severe enough, may necessitate a trip to the emergency room and/or hospitalization.

Tips for Minimizing Bronchospasm in Cold Weather

There is no surefire way to prevent bronchospasm in cold weather, although you can minimize it by following these simple tips:

• Wear a loose-fitting ski/face mask or a scarf over your mouth and nose. A layer of clothing can help warm and humidify the air you breathe, thereby decreasing the irritating impact on your airways.
• Breathe through your nose rather than your mouth. Your nose is better at warming and moistening the cold, dry air than your mouth.
• Avoid getting sick by frequently washing your hands and dressing warmly, including your head and feet. Upper respiratory infections, such as the common cold and flu, are more common in cold, dry air and can be additional triggers of bronchospasm.
• If you have asthma or COPD, keep your rescue inhaler with you. If you experience symptoms of bronchospasm, use your rescue or quick-relief inhaler right away. Also, consider speaking with a healthcare provider about using your rescue inhaler 20 to 30 minutes before going outside in the cold weather.