How Dust Mites Cause Asthma Attacks
Asthma affects millions of people around the world, and the culprit is a bug so small it can't be seen by the naked eye.
STORY AT-A-GLANCE
Dust mites are microscopic, spider-like creatures that live in bedding and furniture, feeding on dead skin cells and producing waste that trigger allergic reactions and asthma
The immune system of allergic individuals mistakenly identifies dust mite waste as dangerous, producing IgE antibodies that trigger symptoms through mast cells releasing histamine
Asthma causes airways to become inflamed and narrow during attacks, making breathing difficult, with dust mites being a significant trigger worldwide according to research
Managing dust mites requires washing your beddings regularly in hot water, using allergen-proof covers, maintaining low humidity and cleaning with HEPA filter vacuums
Dietary changes help manage asthma, including limiting linoleic acid, increasing omega-3 fats and consuming quercetin-rich foods like apples, onions and broccoli
Have you ever woken up with a stuffy nose, itchy eyes and a tight chest? You might blame it on a “morning allergy,” but the real culprit is lurking in your own home — dust mites. These microscopic creatures, invisible to the naked eye, trigger allergic asthma, a condition where your airways become inflamed and narrowed in response to allergens. Specifically, its waste particles, which are found inside dust, cause allergic asthma.1
Meet the Mites — Unseen Inhabitants of Your Home
Dust mites are tiny, eight-legged creatures, related to spiders and ticks. They live around your house but are so small, you can’t see them without a microscope. Imagine trying to spot a grain of sand from across a football field — that’s how small they are relative to us. They thrive in places where dust accumulates, like bedding, carpets, upholstered furniture and even curtains.
These microscopic creatures have a specific diet — they feed on dead skin cells that humans and pets constantly shed. Think of them as tiny recyclers of our homes, breaking down organic matter. While this might sound a little unpleasant, it’s a natural part of a home’s ecosystem. They don’t bite or sting, and their presence is usually unnoticed unless someone is allergic to them.
Dust mites go through several life stages — egg, larva, nymph and adult. They prefer warm, humid environments, which is why they thrive in bedding and mattresses because they find warmth and moisture from our bodies. This is also why controlling humidity in the home is important in controlling dust mite populations.
A common misconception is that dust mites bite humans. This is not true. The problem isn’t the mites themselves, but their waste products — droppings and decaying body parts. These tiny particles become airborne and are inhaled, triggering allergic reactions in asthmatic individuals.
The Body's Misguided Defense When Allergies Strike
The human immune system functions like an army protecting a castle, constantly guarding against harmful invaders like bacteria and viruses. When these invaders enter the body, the immune system recognizes them as threats and launches an attack to eliminate them. This is a normal and essential process for staying healthy.
However, in people with allergies, the immune system makes a mistake. It identifies harmless substances, like dust mite waste, as dangerous invaders. This overreaction triggers a series of events that lead to allergy symptoms. Going back to the castle analogy, think of it as the army mistaking a friendly visitor for an enemy and launching a full-scale attack.
A key player in allergic reactions is IgE, which is a type of antibody. When someone is first exposed to an allergen like dust mite waste, their body produces IgE antibodies specific to that allergen.2 These antibodies attach to mast cells, which are found in tissues throughout the body.
The next time the person is exposed to the same allergen, the allergen binds to the IgE antibodies on the mast cells. This triggers the mast cells to release histamine and other chemicals that cause the familiar allergy symptoms — sneezing, runny nose, itchy eyes and skin rashes. For some, it causes asthma. If not managed properly, your list of allergies will eventually grow longer:3
“Many patients who initially have a single allergic disorder, such as atopic dermatitis, eventually develop others, such as allergic rhinitis and allergic asthma (this is called the allergic march or atopic march).
This process may be driven in part by a vicious circle in which allergic inflammation diminishes the function of the epithelial barrier. This increases the immune system’s exposure to the original allergens and additional allergens, and existing allergen-specific IgE contributes to sensitization to new allergens.”
Asthma's Impact — Tight Airways, Troubled Breathing
Asthma is a chronic respiratory condition that affects the airways, which are the passaged carrying air in and out of the lungs. When it strikes, these airways become inflamed, making it difficult to breathe. Imagine trying to breathe through a thin straw — that’s what it feels like to have an asthma attack.
During an asthma attack, the lining of the airways becomes swollen. The muscles around the airways also tighten, further narrowing the passage. This makes it harder for air to flow in and out of the lungs, leading to several uncomfortable symptoms.
Common symptoms of an asthma attack include wheezing (a whistling sound when breathing), coughing, chest tightness and shortness of breath. The magnitude of these symptoms range from mild to severe, which will significantly impact a person’s quality of life. Again, dust mite is a common allergen for asthma attacks, as noted in a study published by the European Journal of Allergy and Clinical Immunology:4
“It is now recognized that house dust mites (HDM), such as Dermatophagoides (D) pteronyssinus or D. farinae, are the source of the most important indoor allergens associated with asthma worldwide and lead to the development of high-titer allergen-specific IgE.
Substantial evidence associates allergic conditions such as asthma, allergic rhinitis (AR), atopic dermatitis (AD) with exposure to house dust mites (HDM), or other indoor allergens.”
In addition, it's important to understand the difference between allergies and asthma. Allergies are the initial immune response to a trigger, like dust mites. Asthma is a chronic lung condition where the airways are overly sensitive.
Dust mites trigger allergic reactions that then cause asthma symptoms in susceptible individuals. So, while not everyone with dust mite allergies will develop asthma, dust mite exposure is a significant trigger for asthma attacks in those who are predisposed.
Practical Steps for an Asthma-Free Home
There are several effective strategies for reducing dust mite exposure to help manage asthma symptoms. One of the most important steps is to create an environment that reduces dust mites in your home. Start by regularly washing your bedding, including sheets, pillowcases and blankets, in hot water to kill dust mites.5
Using allergen-proof mattress and pillow covers creates a barrier that prevents dust mites from infesting your bedding. Regularly vacuuming with a HEPA filter vacuum cleaner helps to trap dust mites and their waste products, preventing them from becoming airborne. Maintaining low humidity levels (below 50%) in your home will also help to reduce dust mite populations, as they thrive in humid environments.6
Regular cleaning, especially in bedrooms and living rooms, is essential. Pay close attention to areas where dust tends to accumulate, such as carpets, rugs, upholstered furniture and curtains. Dusting surfaces with a damp cloth will help to trap dust rather than spreading it around. Allergy testing will help identify additional triggers, such as:7
Pets — Exposure to dander, which are flakes of your pet’s skin, as well as fur, urine or saliva will trigger asthma.
Pollen — A powdery substance released from trees, grass and weeds. Tree pollen and grass pollen are at their highest during spring, while weed and ragweed have high pollen levels during fall.
Mold — Fungi that form into mold release spores that trigger asthma when inhaled.
Cockroaches — Exposure to droppings, as well as discarded body parts of cockroaches, will trigger asthma.
Food — It’s possible to be allergic to any food, but the most common sources of food allergies include soy, wheat, peanuts, eggs, fish and shellfish.8
Fix Your Diet to Help Manage Asthma-Related Inflammation
At its core, asthma is an autoimmune disease, and one of the most important strategies to managing it is optimizing your mitochondrial function. One of the most important steps to take is minimizing your intake of linoleic acid (LA), which is found in vegetable oils used to cook most ultraprocessed food. Furthermore, vegetable oils come in different forms, and it’s important to familiarize yourself with them. The most used ones include:
Soy
Corn
Canola
Safflower
Sunflower
Peanut
To protect your health, I recommend you limit your LA intake to 5 grams a day. If you’re able to get it to less than 2 grams a day, that’s better. This is the best approach to follow since your body needs some LA anyway. If you want to know how much LA you’re eating, enter your food on Cronometer.com, making sure that it is accurately weighed. The next step is to cook your own food at home using healthy fats, such as ghee, grass fed butter and coconut oil.
Removing vegetable oils and replacing them with healthy fats is just the start. Additional dietary strategies include:
Slightly adding more omega-3 fats — One study evaluated the results of 695 pregnant women after using either a fish oil or olive oil supplement in the last trimester of their pregnancy. The researchers followed these babies for the first five years of their life.
They found the children whose mothers took the fish oil supplement had a 30.7% lower risk of asthma when compared to the children whose mothers took the olive oil.9 That said, be sure to lower your LA intake before upping your omega-3 intake because it’s still a polyunsaturated fatty acid (PUFA).
Essentially, if there’s excess PUFAs in your system, omega-3 will eventually cause metabolic damage similar to LA. So, if you’re pregnant, it would be wise to minimize LA intake and slightly upping your omega-3 intake to achieve a balanced omega-6 to omega-3 ratio.
Drink raw milk — The health benefits of raw milk are hitting mainstream consumers, and there’s research to back the claims. In one study, which followed 983 infants from rural areas throughout Europe during their first year of life, researchers showed that children who drank raw milk had a 30% lower risk of respiratory infections and fever compared to those who did not.10
Increase your vitamin D levels — Research has shown that a higher intake of vitamin D-rich foods during pregnancy helps lower the risk of asthma11 and rhinitis12 in children. However, sunlight is still the best source of vitamin D. For a detailed guide for safe sun exposure, read “The Role of Vitamin D Deficiency in Mental Illness.”
Add Quercetin to Your Diet
After you’ve minimized LA intake, consider adding more quercetin into your diet. Essentially, quercetin is a plant pigment that falls under the flavonoid group, and research shows that this bioactive compound will help manage the symptoms of asthma. In a study published in the Journal of Functional Foods, researchers noted that quercetin exhibits anti-inflammatory properties that support the airways:13
“Asthma's fundamental etiology is a typical Th2 condition marked by increased IgE levels, and eosinophilic airway inflammation decreases the generation of Th2 cytokines, mucus, and eosinophil infiltration in the lung tissue …
Quercetin can regulate the Th1/Th2 balance, inhibit Act1 expression, reduce eosinophil infiltration and airway responsiveness, lower cytokine production, lower IgE production, and improve chronic histopathological changes. Furthermore, it has been demonstrated that quercetin nanocrystals have a strong anti-asthmatic potential at a far lower dose than bulk quercetin …
Additionally, quercetin has anti-inflammatory effects on neutrophilic airway inflammation and has the ability to block Ca2+-permeant channels, which prevent the smooth muscles of the airways from pre-contracting. Quercetin may also help treat asthma symptoms while lowering the need for short-acting -agonists.”
Now that you know how quercetin helps manage asthma, what’s the best way to get it? The great thing about quercetin is that it’s found in various whole foods rich in nutrition. These include green leafy vegetables, citrus fruits, blueberries, cranberries and green tea. In particular, the ones with the highest levels are found in apples, especially the skins, as well as onions and broccoli.14
Quercetin is also available in supplement form. To maximize its effectiveness, Dr. Sin Jung, a chiropractor, suggests taking 500 to 1,000 milligrams two to four times15 a day to protect yourself from allergy-induced asthma.16 For even better results, I recommend combining quercetin with stinging nettle, vitamin C, vitamin D or ginger.17
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