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Indoor Air Quality and Respiratory Illness

Indoor Air Quality and Respiratory Illness

By Andrea Bartels CNP NNCP RNT
Registered Nutritional Therapist

02 Dec 2022

Indoor Air Quality and Respiratory Illness

Protect Your Airways


The cold of winter spells more time indoors-- exposing us to more concentrated levels of hazardous airborne pollutants and allergens that irritate the lungs and nasal passages.  Did you know this combo of stressors in turn reduces our ability to defend against infectious agents and keep chronic respiratory diseases under control?  It’s not exactly ideal camping season, so before you pitch a tent outside your home, find out how you can realistically help your immune system deal with all this more effectively.  What can be done?


Our nutritional status as well as the quality of the air we breathe can be important modifiable risk factors for both incidence and severity of respiratory illness.  Whether you are currently with or without a lung or sinus affliction, find out what you can do to protect your airways right here. 


Addressing indoor air pollution


Most of us have come to expect that we will experience a respiratory infection or two during winter time. But recurring respiratory infections have been associated with higher levels of air pollution both outside and inside the home or workplace.  Why is this?


As Canadians, we spend about 90 percent of our time indoors.  Consider that poorly ventilated spaces accumulate airborne toxins, forming an invisible chemical soup. Windows get shut once the cold weather hits and aren’t opened until Spring, allowing the build-up of toxic elements off-gassing from new furniture, electronics, carpets or renovated spaces, as well as perfumed household cleaning and laundry products. Then there are the common allergens that make up dust, moulds in damp places and even pet dander.


Individuals with allergies, asthma and other COPDs (chronic obstructive pulmonary diseases) are most vulnerable to indoor air pollution.  That’s because chronic inflammation in the respiratory tract creates permanent changes to the lungs—be it caused by an infection or an asthma attack in a process called ‘airway remodeling’. Whether or not you have been diagnosed with one of these serious conditions, the effects of air pollution are not limited to wheezing, sneezing, congestion, headaches, fatigue and difficulty overcoming airway infections.


Many households are switching from gas stoves back to electric for good reason: concern about long-term health effects.  Gas appliances are a source of indoor air pollution, emitting nitrogen oxide, carbon monoxide and even formaldehyde. In particular, there’s concern over nitrogen oxide--- a types of air pollutant that can aggravate pre-existing lung disease like asthma---particularly in children.

Meanwhile, wood-burning heat sources are not the answer, as they emit obvious smoke or particulate that lodges in the lungs and induces inflammatory damage.


How to support your respiratory system


Only nutrients can build your immune system and maintain your airways. After all, I’ve said it before: infections are not caused by insufficient echinacea nor by elderberry deficiency.


Our immune system is a highly complex network of tissues and cells whose job description is to correctly identify, label, attack and destroy physical threats to our well-being.  Antibodies, neutrophils, phagocytes, T cells, B cells and Natural Killer cells are just a few of the vital cells that do the bulk of the work when we come in contact with an infectious agent. How well they fend off a pathogen depends on how well nourished these cells are.  The respiratory system is the first line of defense against airborne pathogens, so be sure to look after it nutritionally with these tips:


Get enough vitamin C

Humans, primates and guinea pigs are incapable of making vitamin C. That’s why un-supplemented diets lacking in raw fruits and vegetables make us vulnerable to deficiency symptoms such as poor wound healing, bleeding gums, and poor resistance to infection. 

There are several ways that vitamin C fights infectious agents.  It enhances the production, proliferation and mobility of various white blood cells, including those that ‘eat’ pathogens and infected tissue.  Additionally, vitamin C is involved in antibody production, so that we have immunity to bugs the next time they come around.  Plus, as an antioxidant, this vitamin also regenerates other antioxidants like glutathione and vitamin E—resulting in even greater protection against the cellular damage caused by the inflammatory response to infection.  Finally, in high doses, ascorbic acid has also been shown to be toxic to certain pathogens and abnormal cells.  Put all these talents together, and you can see how valuable vitamin C is to your immune system.

There’s an abundance of clinical research on this vitamin when it comes to respiratory illness. Here are just a few highlights:

When it comes to asthma, high fruit and vegetable consumption—the main sources of vitamin C and other nutrients—can make asthma symptoms more manageable. Since asthmatic individuals are more prone to respiratory infections, it makes sense to ensure an adequate daily supply through supplementation. Equally interesting is that a history of regular Vitamin C intake is associated with a  reduced risk of developing asthma in the first place.

In a clinical trial of 715 students aged 18 to 32 years of age, 252 students took 1000 milligrams of vitamin C for the first 6 hours once cold and flu symptoms set in, then 3 times daily after that.  Compared to the control group—who took pain relievers and decongestants instead—the Vitamin C -treated students experienced an 85 percent reduction in symptoms. 

In a randomized controlled double-blind trial, 57 elderly patients that were admitted to hospital with acute bronchitis or bronchopneumonia were given either 200 milligrams of ascorbic acid (vitamin C) or placebo daily.  The results? Those who actually took the vitamin C had significantly better symptom improvement than those taking placebo.

In a meta-analysis of 18 controlled trials involving a total of 2004 patients, the length of stay in the ICU was reduced in those given supplementary vitamin C due to improvements in their status. What’s more, those patients who were put on ventilators for over 24 hours and were given C simultaneously had an 18.2 percent reduction in duration of ventilation (with improvements in their condition). Considering the poor survival rate of ventilated COVID-19-positive patients have had during the COVID-19 pandemic, hopefully this data will inspire further study within the context of the pandemic.

Vitamin C has high compliance because its risk of side effects is minimal—especially if a slow-release format is used such as the corn-free Pure Lab Vitamins Slow Release Vitamin C 1000

Break the Cycle of Allergies and Infection with Zinc

Deficiency in zinc has long been known to increased risk of infection by viral, fungal and bacterial infections.  It’s an essential mineral in the production of all immune cells, like macrophages, neutrophils, T-lymphocytes and natural killer cells. It’s also vital to the complement system that works together with these white blood cells to fight pathogens.

For those who suffer from environmental allergies, winter can bring a triple-whammy: higher exposure to indoor allergens, pollutants, conventional drug-supported management of allergies may increase risk of infection, and infections make allergy symptoms worse. What’s going on here?

ICAM-1 is a chemical mediator of inflammation that’s released when the rhinovirus binds to it in the nose, starting the common cold. But if you have nasal allergies, this increases the levels of ICAM-1 in your nasal passages, which increases the number of places the rhinovirus can bind to and induce infection and inflammation. The infection then increases ICAM-1 further, triggering a worsening of your allergy symptoms, and the cycle repeats itself.  If that sounds hopeless, it’s not. It turns out that zinc can bind to ICAM-1 and prevent the rhinovirus from attaching to it.  This may be the reason that several clinically-controlled studies have found that zinc supplementation decreases the severity and duration of the common cold.

In a 2007 study of elderly adults in 33 different nursing homes, adequate zinc status was associated with decreased incidence and duration of pneumonia.  Similarly, studies using oral zinc supplementation in children with respiratory illness have shown good results with as little as 10 milligrams daily. 

Which type is best?

The answer to this question is always, the type that is well-absorbed and without side effects is best. Each capsule of Pure Lab Vitamins Zinc Glycinate contains 23 milligrams of elemental zinc, bound to the smallest amino acid, glycine—for optimal delivery from the digestive system into the circulation.


Get a kNACk for it

If you’ve ever felt so congested you had to breathe through your mouth, use a puffer or take decongestant drugs, you’ll be interested to read that NAC has the useful ability to reduce the stickiness of mucus, enhancing the clearing of mucus from the airways. This makes NAC a valuable component of any respiratory symptom-management program where congestion occurs. At the same time, NAC protects the lungs from the damaging effects of inhaled pollutants because it is an antioxidant that boosts glutathione, which is important for protecting against tissue damage by these pollutants.

Here’s how NAC has improved lower respiratory tract ailments:

Influenza: a common winter virus, the flu has varying levels of prognosis, depending on the health status of the patient and the strain of the virus.  A group of elderly Italian men and women without lung disease were given 600 milligrams of NAC twice daily for 6 months, with several clinically-significant findings. For one, the NAC was well-tolerated; second, patients had less frequent, less severe and fewer “influenza-like” episodes than those in the placebo group; third, although NAC did not prevent infection with the flu, it “significantly reduced the incidence of clinically apparent disease”.

Chronic bronchitis: mostly commonly experienced by heavy smokers, chronic bronchitis is not an infection; it’s a chronic inflammatory state caused by chronic cigarette smoke exposure. In 2000, a systematic review concluded that oral NAC administration for a minimum of 12 weeks reduces the risk of flare-ups and improves symptoms in chronic bronchitis patients when compared to placebo. While caution should be taken with regards to extrapolating from animal studies, NAC given to cigarette-smoke-exposed mice experienced no thickening of the airway, reduced the formation of unhealthy cellular changes in the lungs and cancelled out the physiological effects of the smoke exposure.


Asthma: This is a chronic lung disease where an inflammatory response to a trigger causes broncho-constriction, swelling of the bronchial tubes and excess mucous secretion that together make it difficult to breathe in and out.  Triggers can include stressors like cold air, emotional stress or exercise, environmental allergens to dust, mould, animal dander or pollens, and sometimes, dietary allergens. Although research is ongoing, asthmatics are promising candidates for NAC therapy because of the lung-protective effects of this antioxidant nutrient.

While there are no intact forms of NAC in food, supplementary n-acetylcysteine is available at clinically supportive dosages. Pure Lab Vitamins NAC is a 600 milligram capsule that may be taken daily, or as per your health practitioner’s instructions.


Don’t Leave Respiratory Health Up in the Air

To put it mildly, breathing is kind of important.  That respiratory illness can be triggered or made worse by breathing bad air might sound obvious now, but what are you going to do about it? Although it can be a daunting task, the first step to better respiratory health is cleaning up your indoor environment. If you can’t do this yourself, ask a friend, or better yet, hire professionals. Here’s a checklist for you, created by the Canadian Lung Association.

Maintaining your immune system is the other key to protecting your airways. The nutritional supplements discussed here can provide further support in a most convenient way. Breathe easy!



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