Health Benefits of Humidifiers and Dehumidifiers

Medically Reviewed by Melinda Ratini, MS, DO on August 12, 2023
3 min read

Humidity is moisture in the air around us. Some places tend to have high humidity, while other places are very dry. Either situation can bring on uncomfortable symptoms, but a couple of at-home devices may help.

Humidifiers can add moisture to the air, while dehumidifiers remove moisture. How do you know which one is right for you?

Humidifiers can be especially helpful if you live in a dry, cold climate. II you use your heating system around the clock, the air in your home may become dry. Without moisture in the air, you may get:

  • Itchy eyes
  • Sore throat
  • Irritated lungs 
  • Dry skin

Humidifiers work in two ways:

  • An evaporator humidifier forces air over the water inside of the unit and blows moisture-filled air into your home. 
  • An atomizer humidifier breaks down droplets of water to form a fine mist.

Some humidifiers can be an add-on to your home's central air unit. They can help spread out the moisture evenly through all of the vents in your home. 

Other humidifiers are portable. They can be small or large, depending on your needs. Smaller units are meant to humidify a single room, while a larger unit has the potential to add moisture to your entire home.

Dehumidifiers work to take moisture out of the air, making it drier. They’re helpful in climates that have high humidity, because they can help prevent mold growth and dust mites.

Dehumidifiers pull air into the system and over very cold coils to draw moisture out of the air. The moisture condenses into water and collects in the system. Before air is pumped back into the room, it is forced over warm coils to return to room temperature.

Central air units do remove some moisture from the air on their own. If you have an efficient unit, you may not need a dehumidifier. Portable dehumidifiers have varying space for water.

Before you buy, consider how often you’ll want to dump out the receptacle. No matter the capacity, the moisture that’s removed from your air depends on the level of humidity. Some days you may see more water, and other days you may see less.

You’ll see ratings on the packages as you shop. The rating tells you how many pints the unit can remove in a 24-hour period at 60% relative humidity and at 80 degrees F.

Humidifiers. If you have dry skin, dry eyes, and other irritations from dry air, a humidifier can ease your symptoms. Even if you don’t have symptoms, you may find dry air to be unpleasant. A humidifier may give you a sense of comfort.

Dehumidifiers. Too much moisture in the air can be just as bad as not enough. Water in the air carries bacteria and other tiny organisms that you breathe in. Taking moisture out of the air may help you get some relief from asthma and allergy symptoms caused by the humidity. Keep in mind that allergies can develop over time, so if you notice your symptoms getting worse, talk to your doctor.

Dust mites and mold thrive in humid places, too. If you have asthma or allergies, these microscopic organisms can irritate your sinuses. When you take away the extra moisture, it keeps the growth of mold and dust mites in check. 

Humidifiers can be hard to set up and use. Since they retain water for adding moisture to the air, you'll need to clean it regularly to prevent mold growth. If you get respiratory symptoms after starting use of a humidifier, turn it off and call your doctor.

Humidifiers that use ultrasound technology make a fine white dust that builds up in your house over time. This is due to the minerals found in tap water. Using distilled water in your unit reduces the amount of dust that collects as a result of humidifying.

Moisture in the unit may cause mold growth if you don’t clean and dry it regularly. You can use bleach to kill any mold and bacteria that collect in the unit as it’s running. If you don’t clean the unit, it may cycle mold spores back out into the air of your home.

If you find that any of your symptoms get worse when you use one of these machines, talk to your doctor.

Show Sources


Children’s Hospital Colorado: “The Hidden Danger of Humidifiers.”

Cleveland Clinic: “How You Can Tell If You Need a Humidifier.”

Consumer Reports: “How to Get the Most From Your Dehumidifier.”

Mount Sinai: “Humidifiers and health.”

University of Rochester Medical Center: “Air Filters, Dehumidifiers, and Humidifiers.” 

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