Can Dehumidifiers Improve Dust Mite Allergies?

I've had terrible allergies for 40 years. I can't even remember what it feels like not to have a stuffy nose, watery eyes, and a tickle in my throat. My most recent allergy tests showed I was allergic to cat and dog dander, olive trees, pollen, and dust mites.

Immunotherapy for environmental allergens

Dust mites are too tiny to be seen by the human eye and live in soft fabrics like upholstered furniture, rugs, and our bedding.

To reduce my allergic reaction to these environmental allergens, I underwent allergy shots (immunotherapy). My sensitivity to dog dander decreased after immunotherapy.

All those years of allergy shots, however, didn't greatly help my cat, pollen, or dust mite allergies. As a result, I accepted that I would have year-round allergies.

It seemed that I would never be able to stop taking over-the-counter and prescription allergy medications, including a daily nasal spray.

Managing indoor allergens

I follow all the recommendations to reduce allergens in my home. I vacuum every week with a HEPA filter vacuum. I dust furniture and surfaces with a damp cloth. I wash my bedding in hot water every week.

After taking my dogs outside, I wipe their paws and coat with a pet wipe. I run an air purifier in my home for most of the day. Unfortunately, these steps have not helped improve my allergies much, either.

Humidity plays a role

It's been a little hot and humid here in southern Virginia, where I live. The rooms upstairs feel much warmer and muggier than the rooms downstairs. My office and bedroom are on the second floor, so keeping that part of my home cool helps me work and sleep better. The warmer rooms also trigger my asthma symptoms. My neighbor suggested I use a dehumidifier to help make the upstairs rooms more comfortable.

Trying a dehumidifier to reduce dust mites

I placed the dehumidifier in the hallway between the 2 upstairs rooms right outside the laundry room. I've never used a dehumidifier before, so I wasn't sure how much water it should collect, but that little machine collected a reasonable amount.

After about 2 weeks of using the dehumidifier, even after the weather cooled down a bit, I was talking with a colleague. She grabbed a tissue and said, "Oh please, excuse me; my allergies are just terrible right now."

My initial reaction was to respond with, "Mine, too!" because my allergies are always terrible. As I was responding, I thought for a moment and realized that, actually, my allergies were not terrible.

I took a deep breath through my nose and was surprised that my nasal passages were clear: no stuffiness. I realized it had been several days since I used my nasal spray. This was an unexpected surprise!

Benefits of dehumidifiers

Since I already used an air purifier, I didn't think the dehumidifier would help my allergies. I was wrong - using the dehumidifier helped to reduce the dust mites in my home. Dust mites thrive in high humidity and multiply when it's humid.¹

I reduced the dust mite allergen levels by reducing the humidity in my home. The Centers for Disease Control and Prevention (CDC) recommends keeping the humidity levels low in your home, between 30 to 50 percent, to reduce dust mites.¹

By removing excess moisture in the air, dehumidifiers can also reduce mold growth. Mold is tricky because it is naturally occurring. Not everyone is allergic to mold, but mold is also an irritant, which can irritate healthy lungs and trigger asthma symptoms.

Getting the levels just right

When you have allergies, you want the humidity to be low enough to discourage mold growth and dust mites but elevated enough that the air is not too dry.

To measure indoor moisture, homeowners can purchase a hygrometer. It is an inexpensive device found in hardware stores and online and works like a thermometer. A hygrometer can help ensure you keep your home at the humidity level that is most comfortable for you.

Have you used a dehumidifier to manage allergies in your home?