How does indoor air quality impact your sleep?

Sleep is essential for both your mental and physical health, as well as your overall quality of life. Continuous sleep deprivation can affect brain function and our heart’s health, as well as increase the risk of dangerous health conditions such as diabetes, obesity, kidney disease and even strokes.

Nowadays, sleep is fairly often the first things to be sacrificed when our schedules fill up. And even when you manage to get a proper night of sleep, indoor and outdoor air pollution can decrease the quality and the health benefits of your snoozing.      

A 2017 study found that people who lived in areas with high levels of outdoor air pollution were 60% more likely to sleep poorly than those in regions with less pollution. And yet another study noticed how poor ventilation can also lead to restless nights and groggy mornings.

Let’s break down the different ways in which poor air quality may affect your sleep, and what you can do to decrease your exposure to air pollution during sleep.

How can air pollutants impact your sleep quality?

It’s widely demonstrated that it feels easier to fall asleep when your bedroom is cool and there is a slight breeze from a fan or open source. Stuffy, warm rooms can make it feel almost impossible to get a good rest because of the temperature difference, as well as air quality between the two scenarios.

Good air ventilation is one of the most significant determining factors of a room’s air quality. If you sleep with your windows and doors close, carbon dioxide levels in your room can rise up to 3,000 parts per million (ppm) while you sleep. This is almost three times the recommended safe levels.

Exposure to elevated levels of carbon dioxide can also lead to lower sleep efficiency (how much time you spend asleep in bed compared to the time you spend awake). A 2016 study found that decreased sleep caused by a poor ventilation can even lead to decreased cognitive function during the following day.

Do mold and allergens affect how well you sleep?

Carbon dioxide is not the only indoor air pollutant that can accumulate in the air during the night if a room’s air is not well circulated. Mold and other allergens can affect your sleep quality by causing allergic symptoms, especially nasal congestion, while you are in bed. 

Many allergy triggers, such as mold, pet dander and dust mites, are normally found in the bedroom and in bedding. When you are constantly exposed to these triggers night after night, you may find yourself experiencing nighttime nasal congestion that leads to insomnia, restless sleep and consequent daytime sleepiness.

The most common sleep-disrupting allergens found in the bedroom are mold, dust mites, pollen, pet dander and cockroaches. Some allergens, such as pollen and mold, may appear and disappear depending on the season. However, many other allergens can be found in the bedroom year-round.

Can pollution from particles disrupt your sleep?

In 2017 at the American Thoracic Society’s annual conference, researchers revealed for the first time that exposure to a specific type of polluting particles, called PM2.5 was linked to an increased chance of low sleep efficiency. The researchers discovered that people living in areas with higher concentrations of PM2.5 were more likely to have disrupted or restless sleep than people with low levels of exposure.

PM2.5 is a type of particulate matter composed by small particles suspended in the air with a width of 2.5 microns or less. The reason why PM2.5 are considered more dangerous than larger particles is because they are small enough to travel deep into the respiratory tract when inhaled. Some of these particles may reach your lungs and even enter your bloodstream.

Prolonged exposure to PM2.5 has been linked to short-term symptoms that include coughing, sneezing, runny nose and shortness of breath, as well as eye, nose and throat irritation. Longer-term effects can also include decreased lung function, worsened asthma symptoms and even increased mortality risk from lung cancer and several heart disease.

Symptoms of PM2.5 exposure can cause breathing issues that lead to disrupted sleep, according to research. Nevertheless, it is possible that the lack of sleep may also be a direct effect of pollution exposure. 

Is air pollution linked to sleep apnea?

Sleep apnea is a sleep disorder that causes your breathing to stop and start again repeatedly while you are asleep. It can disrupt sleep and lead to daytime fatigue, sleepiness and irritability. Sleep apnea is also linked to a range of potentially serious complications, including:

• Type 2 diabetes: Sleep apnea can increase your chance of developing insulin resistance and type 2 diabetes.
• Blood pressure: If you have sleep apnea, you experience multiple sudden drops in your blood oxygen levels throughout the night. This can increase your blood pressure and strain your cardiovascular system, leading to hypertension (high blood pressure).
• Metabolic disorders:Sleep apnea may increase your risk of metabolic syndrome, a disorder associated with high blood sugar and blood pressure, abnormal cholesterol levels, increased waist circumference and increased risk of heart disease.
• Liver problems: Individuals with sleep apnea may experience an increased risk of abnormal results on liver function tests and nonalcoholic fatty liver disease.
• Heart problems:Some types of sleep apnea may increase your risk of heart complications, such as heart attack, stroke and abnormal heartbeats. In people with heart disease, nightly episodes of low blood oxygen are associated with mortality caused by irregular heartbeats.

A recent study found a link between exposure to air pollution and the risk of developing sleep apnea. Researchers noted that odds of having sleep apnea increased significantly with increased exposure to PM 2.5 and nitrogen dioxide in the participants. 

While the study was not enough to unrefutably prove that air pollution causes sleep apnea, the authors are clear to underline how improving indoor air quality can directly contribute to better sleep and overall health.

What can you do to increase indoor air quality while you sleep? 

As we already mentioned, when trying to improve the air quality in your bedroom, one of the most important considerations should be ventilation. While a cool breeze may make it easier to fall asleep, it will not improve air quality unless it comes from a source that is cleaner than your indoor air. Turning on a fan and opening a window or door can help keep carbon dioxide from building up to dangerous levels, but it may not help with other types of pollution. 

To improve your quality of sleep by reducing indoor air pollutants such as volatile organic compounds (VOCs), you must first determine the sources of said pollutants. Removing or frequently cleaning elements in your home that collect and trap dust (filters, vents, curtains, etc.) will go a long way to reducing the number of allergens in your home.

If the air outside your home is more polluted than the indoor air, opening a window could actually increase your indoor air pollution. Depending on the source of your indoor air pollution, opening an interior door may be a better method of ventilation.

You might also consider a more complete and integrated approach through integrating an air purifier to increase the air quality while you sleep.

A silent air purifier can also increase the airflow in your bedroom, while actively replacing polluted air with clean one. Sleeping with an air purifier on can help decrease nighttime air pollution exposure that may affect your quality of sleep. To get the most benefit from your bedroom air purifier, try placing it close to your bed at about the same level as your head (such as on a nightstand). Make sure the air intake is not blocked by a wall or other obstruction.

Removing mold and other allergens at the source

Though ventilation and air purification can help manage levels of airborne allergens in the home, source control will make the biggest impact. For mold, this means getting rid of any sources of standing water — leaky pipes, gaps in window frames, unventilated bathrooms and kitchens. 

If you find mold in your home, use diluted bleach to clean the area and kill the mold growth. As long as the mold growth covers less than 10 square feet (and the mold is not a recurring problem in that area), you should be able to clean it on your own without needing to contact a specialist.

Dust mites are another common pollutant found in bedrooms. Though it is impossible to rid your room of dust mites completely, you can help decrease their presence by reducing the humidity, using dust mite-proof bedding and removing places they like to gather, such as carpets, curtains and upholstered furniture.

Other ways to reduce the presence of allergens in your bedroom include:

• Washing your bedding weekly in warm water;
• Keeping pets — and, therefore, pet dander — out of your bedroom;
• Showering before you go to bed to reduce the amount of pollen and other allergens you bring into the bedroom;
• Dusting regularly with a microfiber or damp cloth that traps allergens instead of kicking them up into the air;
• Removing unnecessary dust-gathering clutter from your room;
• Keeping your windows closed on days when pollen, mold or other outdoor pollution levels are high.

A conclusive note

While it’s clear that poor sleep directly affects our physical and mental health, very few know of the impact of indoor air pollution on our sleep quality. Making sure our home and bedroom are safe and healthy is a crucial step to ensure proper a proper sleep, and we all deserve it.