Does Humidity Affect Allergies?

February 16, 2019

For many people, the return of spring is both a blessing and a curse. While the warm temperatures, green grass and beautiful flowers are welcome, seasonal allergies are not. Humidity levels can impact allergies, because they affect both the person and the allergens.

High Humidity and Allergies

Air that has too much moisture creates a breeding ground for allergens like mildew, mold, dust mites and bacteria. These irritants make their way into your home through the ventilation system, windows, and doors. With the right conditions, like plenty of moisture in the air, they can multiply into whole colonies of allergens within hours.

Dust mites in particular can be a problem in humid areas. It’s actually their feces that are the main allergen, and when there’s high humidity, dust mites feast off of our softened skin cells that naturally slough off, and absorb the moisture in the air through their bodies. This leads to more breeding, and more waste. The American Academy of Allergy, Asthma & Immunology recommends keeping indoor humidity below 50% to keep dust mite populations down.

How Low Humidity Affects Allergies

Dry indoor air can irritate your throat and sinuses, causing symptoms that may seem like allergies, but it’s actually what doctors refer to as non-allergic rhinitis. Because the sneezing and congestion isn’t caused by allergies, typical allergy treatments won’t help. Typically things like nasal irrigation and decongestants work better in these cases than just taking antihistamines.

People with allergic dermatitis can suffer from bothersome dry skin and itching when humidity levels are low. Even if allergies aren’t the issue, dry air can cause the mucous membranes in your nasal passages to dry out, which means they can’t do their job of trapping bacteria, viruses, and allergens in the air. This leaves you more susceptible to the flue, colds or other respiratory issues.

How to Regulate the Humidity in Your Home

While you can’t control the weather, you CAN take steps to regulate the humidity inside your house to help reduce your allergy symptoms. According to the Environmental Protection Agency, the ideal indoor humidity level is 25-40%. Running your air conditioner will help remove excess humidity from the air. If that’s not enough, or it’s too cool to turn on the AC, a dehumidifier will pull moisture out of the air, collect it, and then drain or pump it out of your home. If the indoor air is too dry, a whole-house humidifier will distribute water vapor throughout your home, and it comes with a hygrometer to measure the moisture in the air.