
Controlling your indoor environment, specifically your home humidity, is a critical component of any overall effort to reduce your allergy symptoms. Air that is either too humid or not humid enough can contribute to increased allergy attacks. Here’s how:
Too-Humid Indoor Air Causes Allergens to Thrive
While allergy products like allergy relief bedding and electrostatic dust cloths deal with allergens directly, products that control humidity have an often unseen, but nevertheless significant, impact on two of the most common allergens in your home: dust mites and mold.
Dust mites thrive in humid environments. As you probably know, dust mites eat shed skin cells. When the environment is humid, our skin absorbs this ambient moisture, making these sloughed-off skin cells a feast of softened tissue for dust mites. In addition, high humidity provides dust mites with the moisture that they themselves need.

Ample nourishment means more dust mite feces, the primary component of dust mite allergen, and stronger dust mites, who will propagate accordingly. All in all, humidity is good news for dust mites – which is bad news for any allergy sufferer. The same principle also operates in relation to cockroaches, another household pest whose shed skin cells and feces contribute to allergy problems.
 In light of this high humidity- thriving dust mites correlation, the American Academy of Allergy, Asthma & Immunology (AAAAI) says, “To reduce dust mites, it is important to keep humidity below 50% throughout the home by using a dehumidifier or central or window air conditioning.” In fact, making sure humidity levels are below this 50% threshold drastically reduces dust mite populations; most will die within a few days.
Dust mites aren’t the only allergens that multiply when home humidity is high. Mold growth, another potent allergen, is also a problem when humidity levels rise. It only takes fourteen to sixteen hours of over-moist air to activate dormant colony forming units. Dormant units, which make their way into the home through ventilation systems, are just waiting for the right conditions in order to reproduce.
Because it only takes a matter of hours before colonies (literally) of allergens begin to multiply, it’s important to dehumidify immediately when too-humid conditions occur.
Dry Air Worsens Allergy Symptoms
 While air that is too humid leads to increased dust mite allergen and mold problems, air that is too dry also spells trouble for allergy sufferers.
Firstly, although dust mites may begin to die off at humidity levels under 50%, at levels below 30% relative humidity, allergens dry out. Dust mite allergen, mold, and bacteria that are dried out are lighter and therefore more easily airborne, leading to greater inhalation rates.
In addition, the dry air itself can irritate nasal passages and other mucous membranes, exacerbating allergy symptoms and leading to complications such as sinusitis. Sore throats and dry skin, or allergic dermatitis, are also possible repercussions of too-low home humidity levels.
Allergy relief products, including sinus irrigation products and allergy friendly moisturizers help alleviate these symptoms, but keeping air properly moist through humidification really goes to the heart of the matter and will go far in keeping allergy sufferers comfortable through dry conditions.
Ideal Home Humidity and How to Keep it There
We recommend a relative humidity level between 40% and 50% for allergy sufferers. Many humidifiers and dehumidifiers have built-in hygrometers, or humidity gauges, so that units shut off when optimal humidity levels are reached. However, a stand-alone digital humidity gauge allows you to monitor humidity when you are not running a unit or when you need to check an area that may not yet be receiving humidification or dehumidification treatment.
To keep humidity in check, use portable or mini dehumidifiers like the Eva-Dry Mini Dehumidifiers for areas such in a closet or under the sink. The Air Dryr Portable Dehumidifier or the Eva-Dry Petite Dehumidifier are ideal for small rooms.
For larger areas, check out Danby Dehumidifiers; Haier, Soleus, and Alen Dehumidifiers are also excellent for large, damp areas, such as basements, or for use around the house to reduce overall humidity. Ebac and Dri-Eaz Dehumidifiers remove moisture from the air through refrigeration and are ideal for a variety of special circumstances, including crawlspaces, pool areas, and to alleviate humidity problems in water damaged areas.
For areas of the home or times of the year that pose too-dry conditions, check out our comprehensive selection of humidifiers.
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