Can Humidity Cause Sinus Problems? | A COMPLETE Guide

Can Humidity Cause Sinus Problems? | A COMPLETE Guide

Can Humidity Cause Sinus Problems?

Sinusitis, or sinus infections, occur when the tissues in our sinuses swell or become inflamed.

A stuffy nose and trouble breathing are the first signs of sinus problems. 

As is the case with most other bodily functions, we’re often caught unaware and don’t even notice them when they’re working properly! *Gasp*

There are many factors that influence the proper working of sinuses.

Moreover nowadays, with air humidity being very much within our control, the question then becomes – can humidity cause sinus problems?


The Bottom Line:

How Do Our Sinuses Work?

To answer this question, let's first look at what sinuses actually are and how they work.

Sinuses are chambers in the skull that help air circulation as we breathe it in and out.

In a sense, they are buffer zones that warm up and moisten the air as it goes through the nose into the lungs.

Can Humidity Cause Sinus Problems?

There are four pairs of sinuses:

  • Maxillary (beneath the cheekbones)
  • Frontal (above eyebrows on either side of head)
  • Sphenoidal (on either side of nose)
  • Ethmoidal (between sphenoidal sinuses and the eyes)

They differ in size and shape but have a similar structure – a cavity with a mucous membrane, similar to the nose.

The role of mucus in sinuses

Inside sinuses, the mucous membrane produces about 2 liters of mucus a day, which has two layers: lower (liqud) and upper (gel).

There are tiny hairs (cilia) that constantly wiggle to and fro inside both mucus layers, helping them move along. Mucus is also rich in antibacterial and anti-fungal chemicals produced by our body.

What does mucus do?

As we breathe through the nose, bacteria gets trapped in the mucus and shuffled along where it can do no harm.  

Up to 95% of all harmful liquid droplets, bacteria, dust particles, etc, in the air get caught in mucus in sinuses when we breathe through the nose, as opposed to 50% when breathing through the mouth.

However, when something dangerous does try to get through, we start sneezing. As long as we’re not exposed to too much of the same bacteria, it’s all going to be just fine.

what does mucus do?

Consequentially, it's when mucus gets stuck when there’s swelling that we feel this clogging of sinuses as a stuffy nose or a feeling of pressure.

What happens when mucus can't flow?

Sinuses were presumed sterile until medicine advanced to the point of uprooting this presumption, with sinuses actually harboring a whole array of microorganisms that survive and thrive alongside us.

Our sinuses contain bacteria, with the majority of harmful bacteria being:

  • Firmicutes, also found in the gut and resistant to dry conditions
  • Proteobacteria, pathogens associated with inflammation and asthma
  • Actinobacteria, bacteria that act and look like a fungus
Can Humidity Cause Sinus Problems?

There is a host of other bacteria, including known pathogens, and scientists concluded that a person can carry around harmful bacteria in sinuses even without having sinus inflammation!

But, it seems we have friends in there too.

Good bacteria inside our Sinuses

Also a home to friendly bacteria, these microorganisms normally form a biofilm, preventing intruders from taking hold.

These bacteria need a very specific environment to thrive.

It’s the disruption in this delicate environmental balance for microorganisms living inside the sinuses that can lead to harmful bacteria or fungi overgrowth, resulting in Chronic Sinus Inflammation (CRS).

  • Some bacteria, such as Lactobacillus sakei, have such a powerful protective impact on sinuses that they prevent CRS (even in abundance of harmful bacteria).
  • Propionibacterium acnes is another ally we have. It is a bacteria that secretes bacteriocin, a powerful chemical that destroys both bacteria and fungi.

Thanks to these helpful tenants, any bad bacteria that falls inside the mucus won’t be getting out alive if everything works properly!

Consequentially, what goes to the lungs is clean, fresh air.

People who had CRS had substantially reduced richness, evenness, and diversity of helpful bacteria as compared to controls... and factors such as smoking, antibiotic use and age were found to reduce bacteria diversity in the sinuses .

We already have an air filtration system neatly tucked inside our face, it’s only a matter of having it working properly.

It’s only when the mucus isn’t moving fast enough that we experience trouble, which is again that feeling of a stuffy nose.

Bacteria gets trapped inside mucus that's sitting still. This is when there’s a chance for bacterial overgrowth

When mucus slows down to a crawl and we get exposed to the same bacteria type (such as during the flu season), it starts to overwhelm our defenses and infect the mucus.

Can Humidity Cause Sinus Problems?

Turns out, humidity affects mucus flow

So, what helps mucus flow faster? Humidity! You guessed it.

Tropical climates usually provide the optimal conditions! Mucus flows optimally at 98.6°F (37°C) and 100% Relative Humidity” (RH).

Unfortunately, having a tropical climate is not an option all year around for all of us.

Thankfully, while this may be so, maintaining the humidity and air quality in our home is easily achievable and very much within our control!

Maintaining Indoor Humidity & Air Quality for Sinus Problems

Increasing air humidity:

  • Resolves congestion
  • Eases feelings of itchy eyes and noses
  • Improves sleep quality
  • Affects how much an individual strains their voice, especially when having speaking fatigue

Indoor air quality also affects ones health. Higher indoor air humidity was found to make all sorts of particles in the air stickier. 

This means that inhaled particles (which may be dangerous) will stay trapped inside the person’s mucus and taken care off by good bacteria rather than bouncing from one set of lungs to the other. In the long run, humidity increases air cleanliness, which is good!

Sounds familiar?

We’re circling back to all the ideas we mentioned previously – dry air causes less mucus flow, which triggers the sneezing reflex and causes the residents to expel all the harmful particles from their airways into the air, where others can breathe them in. 

Excessive humidity can cause sinus problems too!

Similarly, environments that are too humid can also be detrimental to people suffering from sinusitis.

This is because the damp environment can promote mold and trap pollutants and dust in the air, which can lead to nasal infections.

This situation is especially worrisome in enclosed spaces with many residents, such as in airplanes and in offices.

If merely one person in such a setting has the flu, the usually dry air makes it spread to everyone in the environment. 

Respiratory infections are also more likely in environments with cold and dry air, especially during winter.

In addition, people who have trouble breathing in sleep (obstructive apnea) were also helped by warm, humid air.

It might very well be that plenty of what we consider diseases and aggressively treat as such are simply warning signs by the body that something isn’t right.

What can you do to prevent sinus problems?

Can Humidity Cause Sinus Problems?

Sinus problems may indicate a combination of: 

  • Dry air
  • Overexposure to certain bacteria
  • Lowering of body temperature
  • A poor diet

Sinuses adore humidity and increasing it will provide temporarily relief. In other words, keep your face warm during winter and find a way to breathe in moist air. 

A humidifier will do just the job.  

Alternatively, simply increasing the temperature of your house may help to alleviate your symptoms.

Nitric oxide (NO) is also another powerful activator of many systems in the body. For example, NO that touches a blood vessel makes it temporarily relax and expand, briefly lowering the blood pressure.

In case of cilia inside sinuses, NO makes them beat faster.

Whence does the body get NO?

The body uses an amino acid L-arginine from foods such as pumpkin seeds, meat, and legumes to create NO, but also veggies, such as beetroot, which have NO2 and NO3 that gets turned into NO by the body as needed.

Conclusion - Can Humidity Cause Sinus Problems?

So, can humidity cause sinus problems? Yes!

Mucus has a role to play in this and it appears a higher humidity helps the mucus flow, keeping sinuses clean and clear.

A fairly established conclusion is that this has to do with the relative humidity inside the sinuses, which helps them tremendously.

However, more research can be done to deepen the consensus of the relationship between humidity and sinuses.

Even our understanding of the body may change (Eg: by considering sinuses an essential part of the lungs that has a crucial role in moistening and filtering the air rather than a separate, trivial organ that randomly gets clogged).

However, what we do know is that each body is wonderfully quirky and reacts to different circumstances in a different way.

We get plenty of warnings that the air around us is too dry – dry, itchy eyes and nose, congested sinuses, flaky skin, cracking voice and many others.

And we should listen to what the body is telling us and react in a relaxed, sustainable way rather than ignoring the discomfort or going overboard with extreme solutions.

Ultimately, we all want to live a more comfortable life and, by the looks of it, increasing relative air humidity is just the thing to help us achieve it.