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A dehumidifier is an appliance that takes moisture out of the air in your home.

If you or your family members have asthma or allergies, a dehumidifier might help relieve symptoms and make breathing easier.

This article will help you decide whether a dehumidifier is a worthwhile investment for your living space.

You may remember the water cycle from elementary school science: evaporation, condensation, and precipitation. What you might not realize is that the water cycle is always taking place in the air you’re breathing, even when you’re spending time inside.

“Humidity” is a measure of water vapor in the air. Dehumidifiers remove or minimize this water vapor.

Dehumidifiers help reduce allergy symptoms

Environmental allergens can cause symptoms like:

  • wheezing
  • sneezing
  • chest pain
  • eye irritation
  • itching

Common allergy triggers include:

  • mold
  • dust mites
  • pollen
  • animal dander

Drying out the air in your home keeps triggers to a minimum.

Dust mites, in particular, need a relative humidity level of 65 percent to survive and procreate. That’s a level that can be easily managed by using a dehumidifier.

Dehumidifying the air also controls mold growth.

Dehumidifiers may help control asthma

When there’s moisture in the air, it becomes heavier and often more difficult to breathe. That’s why high-humidity environments can be difficult for people who have asthma.

A dehumidifier can make the effort to breathe in and out easier on the lungs. Mugginess disappears and the air is cooler and more comfortable.

There’s little evidence to support the use of a dehumidifier as an actual treatment for chronic asthma, according to a 2013 study, but there’s also no evidence that trying a dehumidifier can have an adverse effect.

Dehumidifiers can create a healthier environment

By eliminating mold and dust, you’re also eliminating invaders like silverfish, cockroaches, and spiders. Lower humidity levels may also benefit people who have COPD.

If you live in a naturally humid climate, a dehumidifier can also cool off your home and reduce your air conditioner use.

A dehumidifier works by drawing warm air currents into its coils via a fan. The warm air contracts as it’s fed through the refrigerated coils of the machine, and condensation is left inside the dehumidifier.

As this condensation collects, one droplet of water at a time, it falls into a storage tank attached to the dehumidifier. Cooler, drier air is then released back into your home through the other side of the machine.

Your dehumidifier should be able to bring the moisture in the air down to a relative humidity of 30 to 50 percent. Many dehumidifiers come with a meter that measures the relative humidity where it’s placed in your home, and you can set the humidity to the percentage you desire.

A dehumidifier might not work the same way for everyone. There are some potential side effects to using one in your space.

Dehumidifiers make the air more dry. If you live in an already dry climate (such as a desert or high-altitude area), or use gas or electricity to heat your home, a dehumidifier might not be needed.

Conditions like pneumonia can actually become worse if the air is made too dry.

Your skin and hair can be affected, too, if your home becomes an arid place. People with eczema (atopic dermatitis) may be especially prone to flare-ups in a dry environment.

When you use a dehumidifier, you might need to be especially mindful of staying hydrated.

If you have a dry cough or stuffy nose, running a dehumidifier might do more harm than good, too.

Dehumidifiers work best in areas where damp air collects, like basements. Signs you might want to consider buying a dehumidifier include:

  • Anyone in the home has a prolonged allergy season, year after year.
  • You’ve recently moved and your allergies seem to be flaring up more often or worse than they used to.
  • There’s a persistent damp smell in an area of your home where you frequently spend time.
  • Your space experiences water leakage after heavy rainfall.
  • You notice muggy air in your home when you entire, indicating you can actually see the water vapor in the air.
  • Anyone in the home has an allergy to dust mites.
  • You’ve noticed an increase in unwanted pests, such as spiders, cockroaches, moths, or silverfish.
  • Your clothes smell damp or moldy even when they have been freshly washed.
  • You have persistent symptoms of respiratory illness, such as coughing and runny nose.

You can buy a dehumidifier at almost any home supply retailer or home improvement store. Appliance stores and department stores also tend to keep them in stock.

Before you purchase, you’ll need to know:

  • what tank size you’re looking for (how much water the dehumidifier collects at a time before you need to empty it)
  • what range of humidity the appliance can control

You may also want to figure out the energy costs associated with the appliance before you purchase it.

Buy a dehumidifier online.

A dehumidifier does have some established health benefits. The main benefit is reducing the presence of allergens and irritants in damp areas of your home.

There’s also some indication that a dehumidifier can make breathing easier for people who have asthma.

Dehumidifiers are accessible and easy to purchase. Giving one a try might make a difference in the comfort level you experience at home.