What Is the Best Air Purifier? [Updated: 2025]
One of the top 5 environmental threats to public health, according to the EPA, is indoor air quality.
Many construction materials, wardrobe items, and furnishings — like your mattress, carpet, curtains, and paint — are sources of volatile organic compounds (VOCs). As these materials release VOCs, linked to ill health effects, they adulterate the air we breathe.
Add to that the toxic commercial cleaning agents (which some studies show may be as deleterious for lung health as cigarette smoking) and you have yourself a recipe for pathology.
To make matters worse, we track allergens and pollen into our homes, meanwhile our furry friends generate pet dander, all of which can lend themselves to the development or exacerbation of allergy and atopic diseases (like eczema and asthma).
Needless to say, our home’s air quality can be a significant hindrance in our healing journey.
So, what can we do about it?
In addition to trading your cosmetics and personal care products for nontoxic alternatives, investing in organic and nontoxic furniture, where possible, opting for VOC-free paint, and ensuring your cleaning supplies are nontoxic (I discuss my favorite go-to nontoxic cleaning agents in my article here), investing in a high-quality air purifier is truly a must in this day and age.
This is true more so than ever in the midst of fire season in order to ensure good indoor air quality when being outside in smoky conditions is impossible.
Why an Air Purifier Is So Important: PM-2.5, A Silent Killer
Poor air quality from industrial activities and wildfires liberates enormous levels of particulate matter, including PM-2.5, into the environment.
This is not withstanding the financial toll incurred by particulate matter, which cost China and the United States $106.5 billion and $29 billion, respectively, in one year alone.
Particulate matter consists of biological components such as:
cell fragments and endotoxin
crustal material
heavy metals
particle-bound water
sulfates
nitrates
organic and elemental carbon
dangerous combustion byproducts called polycyclic aromatic hydrocarbons such as naphthalene and benzo(a)pyrene
Anthropogenic, or manmade sources, such as construction sites, cooking, vehicle exhaust, agricultural or industrial byproducts, road erosion, mining operations, and combustion of solid-fuels including coal, oil, gasoline, biomass, and lignite can generate particulate matter.
However, particulate matter production can also emerge from natural sources such as sea spray, vegetation, volcanoes, dust storms, windblown soil, and (most relevant to recent current events) forest fires.
Fine particulate matter (such as PM-2.5), which can be either directly released into the air or converted from gaseous precursors, poses monumental risks to health due to its suspension in air for weeks to months and its ability to be transported hundreds or thousands of kilometers.
In fact, research estimates PM-2.5 reduces lifespan by an estimated 8.6 months.
Smaller particulates like PM-2.5 tend to lodge in the respiratory tract at increased rates, depositing deep within sites of gaseous exchange and ultimately translocating into tissue and circulation.
PM-2.5 air pollution is linked to the following adverse outcomes:
leads to reactive oxygen species (ROS)
damages genetic material
disrupts cell membrane integrity
induction of pro-inflammatory cytokines
It is also linked to the following pathologies:
pulmonary fibrosis
cardiac hypoxia
atherosclerotic lesions
programmed cell death
acute coronary syndrome
hypertension
venous thrombosis (blood clots)
arrhythmia
stroke
exacerbation of congestive heart failure
increased rates of heart attacks
depressed heart rate variability
diabetes
reduced lung function
respiratory-related mortality
increased hospital admissions for pneumonia, asthma, and chronic obstructive pulmonary disease (COPD)
Put simply, our health benefits greatly from reducing our exposure to harmful airborne contaminants, especially PM-2.5.
Best Air Purifier to Remove PM-2.5
So, how can we minimize the risks of PM-2.5 (and other airborne contaminants)?
Alongside a whole food-based diet and functional lifestyle changes, reducing the contaminant burden of indoor air is an immensely helpful strategy.
Personally, I use an AirDoctor Pro professional quality air purifier to mitigate the risk of PM-2.5. AirDoctor Pro is 100x more effective than ordinary HEPA filters—considered the gold standard.
While HEPA systems only claim to remove particles down to 0.3 microns, AirDoctor UltraHEPA™ is certified to filter 99.99% of all particles down to 0.003 microns (100 times smaller).
The AirDoctor Pro also:
Combines UltraHEPA filter with dual action Carbon/Gas Trap/VOC Filter
Auto-Mode uses a professional-grade sensor to adjust filtration speed to ambient air quality
Uses exclusive Professional WhisperJet fans (30% quieter fans than ordinary air purifiers)
Features an Air Ionizer which can be turned on or off, that removes particulates, microbes, and odors from the room to leave it smelling fresh
Boasts a 100% sealed system to ensure all the air you breathe is pure and filtered
Formaldehyde: Another Indoor Air Quality Concern
A colorless, strong-smelling gas used in household products and building materials, formaldehyde is identified by the EPA as a "probable carcinogen".
Potential sources of formaldehyde are all around us, including from:
Pressed-wood products, such as particleboard, plywood, and fiberboard
Cooking emissions from gas stoves and kerosene space heaters
Glues and adhesives
Permanent-press fabrics
Cigarette smoke
Vehicular exhaust
Some insulation materials
Clothing and bed linen
Plastic food containers
Personal cafe products and cleaning agents
Toxic chemicals, including formaldehyde, may be important triggers for autoimmunity, as revealed by Vojdani and colleagues.
I have personally had functional materials reactivity testing and chemical immune reactivity screening demonstrating that each time I am exposed to formaldehyde, the autoimmune response in my body is amplified.
This response is not uncommon, as exemplified in this article by Dr. Isabella Wentz.
In fact, as outlined in their article, only 30% of autoimmune diseases are attributable to a genetic component, with the remaining 70% the result of environmental factors, including toxic chemicals, dietary antigens, gut dysbiosis, and infections. This is why minimization of these exposures is so important not only to prevent, but to potentially help ameliorate the pathogenesis of autoimmunity.
Luckily, formaldehyde is not the only VOC removed by AirDoctor Pro — it also removes virtually 100% of airborne particles, but also the vast majority of toxic ozone, VOCs and gases.
Air Filtration: What About Pathogens?
The following information was relayed to me by AirDoctor Pro to provide clarity on a question that is on many people's minds.
Note: It is not meant as medical advice, diagnosis, or treatment and is for educational and informational purposes only.
Standard HEPA purifiers are 99.97% effective at capturing particles as small as 0.3 microns, but they are not tested to capture virus-sized particles.
Although it has not been evaluated for its ability to capture COVID-19, AirDoctor’s UltraHEPA filters have been independently tested to capture 100% of airborne particles at 0.003 microns in size.
Viruses can range in size from 0.004 to 0.1 microns in size.
According to Dr. Mariea Snell, the Assistant Director of Doctor of Nursing Practice Programs at Maryville University, the size of the coronavirus is approximately 0.125 microns.
Please note: While AirDoctor has been shown to capture particles as small as COVID-19, it has not yet been tested for this virus. Until such testing is available and completed, AirDoctor does not claim to be effective at removing or killing COVID-19.
However, in a standardized test room, AirDoctor Pro removed 99.99% of a range of bacteria and viruses.
What is the cost of the AirDoctor Pro Air Purifier?
Normally, the AirDoctor Pro is $629, but when you shop through my affiliate link, you get a $300 off discount (nearly 50% savings) for a price of $329.
Some of the competitors are listed below, demonstrating the arenas in which AirDoctor is superior and reasons why I chose this brand over the others.
I myself have past experience with another one of the popular units on this list, about which I am often asked, and chose to replace it with the AirDoctor due to a prominent chemical off-gassing smell whenever I ran the unit. I currently have two AirDoctor units and have not had any issues of that nature with either.
How many air purifiers do I need?
How many air purifiers you need depends on the square footage of your home. The AirDoctor Pro can filter the air in a 900 square foot room 3x an hour, or a 450 square foot room 6x an hour.
I personally recommend at least one unit per story of your house. It is important to have air purification in bedrooms, where we spend the majority of our time, and in a common living room/kitchen area, given the harmful byproducts generated by cooking. I would argue that air purification is especially important in the vicinities where children spend their most time, since their delicate developing bodies are most sensitive to toxic exposures.
I know several moms have contacted me to tell me that they donated units for their children's classrooms, which is a fantastic idea given that many schools now have ramped up policies for classroom use of sanitizers and disinfectants--many of which are EPA-registered pesticides--in the era of COVID.
Lastly, cooking is one of the biggest contributors to poor indoor air quality--generating carbon monoxide, volatile organic compounds (VOCs), and polyaromatic hydrocarbons with proven carcinogenic properties as well as fine particulate matter (including the most damaging PM- 2.5) — and ventilation systems are oftentimes inadequate, which is why I keep a unit by the kitchen.
Air Filter Replacement: How Much Is It?
The AirDoctor Pro comes preloaded with the both the filters it requires. There is also a 3rd pre-filter, which can be easily removed and washed. With proper care and under normal operating conditions, manufacturers state that this filter should not need to be replaced.
The unit also has an automatic sensor which notifies you when it is time to replace the Gas Trap VOC filter and the UltraHEPA™ filter, both of which are available for $59.95 each, plus shipping and processing.
How long your filters last is contingent upon the prevailing air quality in your home and how many hours per day you operate your unit. According to the company, "Based on the air quality in the average home in the United States and Canada and 24/7 operation, the Gas Trap VOC filter should last 6 months and the UltraHEPA™ filter should last a full 12 months before they need to be replaced."
If you operate your unit for only 12 hours per day, then the Gas Trap VOC filter should last 1 year and the UltraHEPA™ filter should last a full 2 years before they need to be replaced (in homes with average air quality). We recommend that you leave your AirDoctor set to Auto, which will allow your device to adjust automatically, based on the filtering needs inside your home."
Thus, it is relatively low cost to maintain. It also only consumes 11 watts of electricity on the low setting and 95 watts on the high setting, meaning that on average, it costs about $30-40 per year to run on Auto-mode 24/7 (although utility costs will vary).
Other Tips To Promote Improved Air Quality
Besides using an air purifier to reduce your toxic load, there are other strategies you can use to improve indoor air quality.
Keep your windows open as much as possible for adequate air circulation (in the absence of fires, and as long as outdoor air quality is good. Check outdoor PM-2.5 level with Purple Air and Air Quality Index with Air Now).
Ensure you have a carbon monoxide detector and have your house checked for radon.
Green-up your house with air purifying house plants (I discuss some studied by NASA in my article here on home detoxification).
Get rid of indoor air fresheners, Febreeze sprays, perfumes, colognes, and non-soy candles, which contain artificial fragrances that not only pollute your home but hijack your hormones.
When should you invest in an air purifier?
I didn't take the leap and get an air purifier until nearly a decade into my struggles with chronic illness. Having listened to so many podcasts, summits, webinars, seminars, and attended myriad trainings, I knew it was one of the top recommendations by naturopathic and functional medicine practitioners, but for years, my finances did not allow it, and I prioritized health-related budget toward food and targeted supplementation.
While both of these were instrumental in my recovery, I wish I had bit the bullet sooner and gotten myself high quality air and water purification systems--since clean air and water are prerequisites to health and survival, even before food. One clinical pearl that has always stood prominent in my mind was what Dr. Walter Crinnion, the late great environmental medicine physician, said in my Detoxification and Biotransformation course in my Master's program--that one of the first steps he undertakes with autoimmune patients was filtering their air (alongside removing carpet if possible, since it is a major source of toxicity).
My point being, if this is within your budget, I highly recommend it. There are few companies I so whole-heartedly stand behind, and receive so many amazing testimonials from my followers about.
There is no "correct" order for transitioning to a more holistic, low toxin lifestyle, and the order in which you embark upon the changes you make ultimately comes down to priorities and personal preference.
However, speaking from my own experience, I wish I had invested sooner in air and water purification knowing the benefits I have witnessed in my own health.
