We often think about fresh air as something we enjoy outdoors. A morning walk, time in the garden or a few minutes on the porch can feel refreshing.
But what about the air inside our homes?
We spend a significant part of our lives indoors, where air quality is influenced by ventilation, humidity, dust, cleaning products and our heating and cooling systems.
These everyday factors deserve attention, particularly as the seasons change and we begin spending more time inside.
What Affects Indoor Air Quality?
The air inside our homes contains particles and gases from both indoor and outdoor sources.
Cooking, household dust, pets, furnishings, fragrances and cleaning products can all contribute to indoor air pollution. Without adequate ventilation, some pollutants can build up over time.
Certain exposures can irritate the eyes, nose and throat or aggravate existing respiratory conditions, particularly in people with allergies or asthma.
Improving indoor air quality doesn’t mean eliminating everything from our environment. It starts with understanding where potential problems come from.
Heating, Cooling and Air Ducts
Our heating and air conditioning systems do more than regulate temperature. They also move air throughout the home, making regular maintenance important.
Air filters capture particles as air passes through the system. When filters become clogged, airflow can be restricted, so they should be checked and replaced according to the manufacturer’s recommendations.
It’s also worth checking vents and return grilles for dust buildup.
But what about the ductwork we cannot see?
Over time, debris can accumulate inside ducts. While some dust is normal, substantial buildup, pest contamination or visible mold growth warrants professional attention.
A qualified HVAC or duct-cleaning company has specialized equipment to inspect and clean areas homeowners cannot easily reach. Restoration companies can also assist when moisture damage or contamination is involved.
Professional duct cleaning isn’t required on a fixed schedule for every home. An inspection can help determine whether cleaning is necessary, particularly after water damage, pest problems or renovations.
For additional information, the Environmental Protection Agency explains when air duct cleaning should be considered.
Air Conditioning and Our Ability to Adjust to Temperature Changes
Have you ever been sitting in a restaurant during the summer, feeling so cold that you wished you’d brought a sweater, only to step outside into 100°F heat?
It’s quite a temperature change, and our bodies have to respond.
Our nervous system plays an important role in regulating body temperature through changes in circulation, sweating and other physical responses. Over time, our bodies also adapt to the temperatures we’re regularly exposed to, a process known as acclimatization.
According to University of Iowa Health Care, spending most of our time in air-conditioned environments can make it more difficult to tolerate outdoor heat. Age, physical condition and certain medications can also influence how well we adjust.
Cold, dry indoor air can contribute to discomfort such as dry eyes, irritated nasal passages and headaches in some people. Sudden changes in temperature can also trigger a runny nose or other nasal symptoms.
Years ago, an experienced professional shared a practical rule of thumb with me: during the summer, try to keep the indoor temperature no more than 10–20°F below the outdoor temperature. Of course in extreme heat, the difference can be greater.
Keeping the thermostat a little higher can also reduce electricity consumption and lower cooling costs.
Of course, humidity and individual health needs still matter, particularly during extreme heat. The goal isn’t to keep our homes excessively warm, but to avoid unnecessary overcooling and allow our bodies to maintain their natural ability to adjust to seasonal temperatures.
Humidity, Dust Mites and the Bedroom
Humidity affects both comfort and indoor air quality.
Air that is too dry can irritate the eyes, nose and throat. Excess moisture encourages mold growth and creates favorable conditions for dust mites.
An indoor humidity level of approximately 40-60% is generally recommended.
Bedrooms are especially important because of the amount of time we spend sleeping.
Dust mites commonly live in mattresses, pillows and bedding. Their allergens can contribute to respiratory and allergy symptoms in sensitive individuals.
Washing bedding regularly, controlling humidity and using allergen-resistant mattress and pillow covers when needed are practical ways to reduce exposure.
For a closer look at how dust mites affect our indoor environment and what you can do to reduce exposure, read my article on
dust mites and creating a healthier bedroom.
Fragrances, Cleaning Products and Cooking
A home that smells clean doesn’t necessarily have clean air.
Scented candles, air fresheners, essential oil diffusers and fragranced cleaning products can release substances into the air. Some people are particularly sensitive to these exposures.
Choosing fragrance-free products and ensuring good ventilation while cleaning can help.
Cooking is another source of indoor air pollution. Both gas and electric cooking can produce airborne particles, while gas appliances can also release combustion-related pollutants.
Using a range hood that vents outdoors helps remove pollutants and moisture while cooking.
Fresh Air and Ventilation
Fresh outdoor air can help dilute pollutants that accumulate indoors.
Opening windows when outdoor conditions are suitable is one option. However, during periods of high pollen, smoke, outdoor pollution or excessive humidity, keeping windows closed can be preferable.
Kitchen and bathroom exhaust fans help remove moisture and pollutants directly from the areas where they are produced.
Portable air purifiers with HEPA filters can also reduce airborne particles, although they don’t replace proper ventilation or moisture control.
The important thing is finding an approach that suits your home and its surroundings.
Looking at the Bigger Picture
When we think about supporting our health, nutrition, movement, hydration and sleep often come first.
But our surroundings are part of the picture too.
In my holistic practice, I consider environmental influences alongside a person’s health and lifestyle history. Sometimes, connecting the dots means looking at everyday exposures that haven’t received much attention.
Small changes can be a good starting point: checking an air filter, monitoring humidity, improving ventilation or reconsidering the products we use around the house.
Supporting our health isn’t always about adding more. Sometimes it’s about paying closer attention to what we’re already exposed to every day.
