The Nose Knows
Supporting the Nasal Passage During Cold & Flu Season
Back-to-school season means new classrooms, new routines, new friends...and a whole lot of new germs.
When we think about supporting the immune system during cold and flu season, we tend to immediately think about vitamin C, vitamin D, zinc, sleep, and nutrition. Those things matter, but there is another piece of immune health that deserves much more attention:
The nose.
Your nasal passages aren't simply tubes that move air into your lungs. They are an active part of the body's innate immune system and one of the first places the body interacts with viruses, bacteria, allergens, dust, and other particles in the environment. Think of your nose as the front door of your immune system.
In fact, the nose is a major site where common respiratory viruses first encounter the body. Its anatomy helps filter inhaled particles and deposit them in the upper airway, where several layers of immune defense immediately go to work.
That makes nasal health an interesting and often overlooked part of supporting the body during the school year.
Your Nose Is More Than an Airway
Every time you inhale through your nose, air passes across a specialized mucosal surface covered in mucus and microscopic hair-like structures called cilia.
Think of this system as a combination of a filter, conveyor belt, and immune surveillance station.
Mucus helps trap particles that enter the nose, including:
Viruses
Bacteria
Allergens
Dust
Environmental pollutants
The cilia then continuously move that mucus toward the back of the throat, where it can eventually be swallowed and exposed to the gastrointestinal tract.
This process is known as mucociliary clearance, and it is an important component of our first-line respiratory defenses.
But the nasal mucosa does even more.
Cells lining the airway participate in immune signaling and help recognize potential pathogens. In other words, the immune system doesn't wait until a virus has traveled deep into the body before responding. Surveillance begins right at the body's front door.
The goal isn't to sterilize the nose.
That's an important distinction.
Your nasal passages have their own normal microbial environment, just like the gut and skin. Supporting nasal health isn't about aggressively disinfecting your nose every day.
Instead, the goal is to support the mechanisms your body already uses to:
trap → identify → clear → respond
That brings us to nasal hygiene.
Nasal Hygiene: The Handwashing of the Upper Airway?
We routinely teach children to wash their hands after school, but nasal hygiene receives considerably less attention.
Saline nasal sprays and rinses can help physically remove mucus, allergens, dust, and accumulated material from the nasal passages while keeping the mucosal surface hydrated.
Research in children with upper respiratory infections suggests saline nasal irrigation may improve nasal symptoms, although the evidence for broader respiratory benefits is still limited and more research is needed.
For families, there are several ways to incorporate gentle nasal care.
1. Simple Saline Nasal Spray
For everyday use, a sterile saline nasal spray may be the simplest option.
Unlike medicated decongestant sprays, plain saline primarily works mechanically. It helps moisturize dry nasal tissue and loosen mucus and debris so the nose can clear it more effectively.
This can be particularly useful during an Alaska winter or anywhere indoor heating creates extremely dry air.
A simple routine might be:
After school → wash hands → change clothes if desired → saline nasal spray → blow nose gently.
It doesn't need to become complicated.
For younger children, always choose an age-appropriate product and follow the manufacturer's directions.
2. Nasal Irrigation
Older children and adults may prefer a more thorough saline rinse using a squeeze bottle or neti-style irrigation system.
Irrigation provides considerably more volume than a nasal mist, helping flush mucus and accumulated material from the nasal cavity.
But there is one extremely important safety rule:
Never use ordinary tap water directly in a nasal rinse.
Tap water can be safe to drink without being sterile enough to introduce directly into the nasal passages.
The CDC recommends using distilled, sterile, or previously boiled and cooled water for nasal irrigation. Rare but extremely serious infections have occurred after people used contaminated tap water for nasal rinsing.
If boiling tap water, the CDC recommends bringing it to a rolling boil for at least one minute and then allowing it to cool before use.
Also clean and dry your irrigation device according to the manufacturer's instructions.
3. Xylitol Nasal Sprays Like Xlear?
Another option that has become increasingly popular is xylitol-containing nasal spray.
Xylitol is a naturally occurring sugar alcohol. In nasal products, it is combined with saline and used to moisturize and cleanse the nasal passages.
There is legitimate research behind xylitol nasal irrigation.
Randomized studies have found that xylitol nasal irrigation can improve symptoms in people with chronic rhinosinusitis, and a 2026 systematic review found improvements in subjective sinonasal symptoms compared with saline in some populations.
Research has also investigated potential effects of xylitol on bacterial adhesion and the local nasal environment.
Products such as Xlear may be useful as part of a nasal-hygiene routine, particularly for moisturizing and cleansing the nasal passages, but they should be viewed as one supportive tool rather than an antiviral shield.
For children especially, age matters. One randomized study of children with chronic rhinosinusitis found that xylitol irrigation was less well tolerated and did not recommend it as first-line treatment for that population.
Plain sterile saline is therefore a reasonable place to start.
Supporting Immunity Beyond the Nose
Nasal hygiene is only one layer of immune support.
Our immune system is incredibly resource-intensive, and children need adequate nutrients and recovery to mount an appropriate immune response.
During the school year, focus on the foundations:
Sleep
Children need considerably more sleep than adults. Consistent bedtimes become especially important once school schedules, sports, homework, and extracurricular activities return.
Protein
Immune cells, antibodies, enzymes, and tissues require amino acids. Build meals around quality protein sources such as eggs, meat, poultry, fish, Greek yogurt, beans, and other whole-food options.
Vitamin D
Vitamin D plays an important role in normal immune function. In northern climates, maintaining adequate vitamin D becomes particularly relevant as daylight rapidly decreases during fall and winter.
Rather than blindly taking large doses, consider discussing vitamin D testing and age-appropriate supplementation with your healthcare provider.
Vitamin C
Vitamin C supports numerous immune functions and is abundant in whole foods including berries, citrus, kiwi, peppers, broccoli, and potatoes.
Zinc
Zinc is essential for normal immune-cell development and signaling. Foods such as beef, shellfish, eggs, dairy, pumpkin seeds, and legumes can contribute dietary zinc.
More isn't necessarily better. Excessive supplemental zinc can cause problems, including copper deficiency, so long-term high-dose supplementation shouldn't be used casually.
Hydration
Mucosal surfaces need adequate hydration. Encourage children to drink water throughout the day rather than arriving home dehydrated after school.
Movement and outdoor time
Regular physical activity supports overall metabolic and immune health, while outdoor time also provides something children desperately need during the school year: movement, daylight, and a break from indoor environments.
What About Antiviral Nasal Sprays?
There is growing research around nasal products designed to create an additional physical or chemical barrier against respiratory viruses.
For example, iota-carrageenan nasal sprays have been studied for the common cold. In one randomized controlled trial, adults with laboratory-confirmed viral colds using a carrageenan spray experienced faster symptom resolution and greater reductions in nasal viral load than the saline comparison group.
This is an interesting area of research, but it is still evolving.
The Bigger Picture: Support the Barrier
We spend a lot of time talking about "boosting" the immune system.
A better way to think about immune health may be supporting the barriers and systems the body already has.
Your skin is a barrier.
Your gastrointestinal tract is a barrier.
And your nasal and respiratory mucosa are barriers too.
The nose isn't simply where congestion happens when you're sick. It is part of an incredibly sophisticated defense system constantly sampling the environment, trapping particles, moving mucus, and communicating with the immune system.
So this school year, alongside the lunch boxes, backpacks, vitamins, and earlier bedtimes, consider adding one more simple habit:
Take care of the nose.
Keeping nasal passages comfortably hydrated, supporting normal mucociliary clearance, using saline or other appropriate nasal products, and practicing safe nasal irrigation may be another practical way to support the body's natural defenses during the months when respiratory viruses are circulating heavily.
A Note on Nasal Rinse Safety
Only use commercially prepared sterile saline or distilled, sterile, or properly boiled-and-cooled water for nasal irrigation. Never use untreated tap water directly in a neti pot or sinus-rinse bottle. Children should use nasal products appropriate for their age and under adult supervision. People with recurrent nosebleeds, recent nasal surgery, significant sinus disease, immune suppression, or other medical concerns should talk with their healthcare provider before beginning regular nasal irrigation.
Medical Disclaimer
This article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent disease or replace individualized medical advice. Talk with your healthcare provider about recommendations appropriate for you or your child.
References
Centers for Disease Control and Prevention. How to Safely Rinse Sinuses. CDC, 2025. Guidance on using distilled, sterile, or boiled-and-cooled water for nasal irrigation and avoiding untreated tap water.
CDC: How to Safely Rinse SinusesEccles R, et al. Efficacy of a Carrageenan Nasal Spray in Patients with Common Cold: A Randomized Controlled Trial. Respiratory Research. 2013;14:124. In adults with laboratory-confirmed viral colds, carrageenan nasal spray was associated with faster symptom resolution and greater reduction in nasal viral load compared with placebo.
Read the studyFazekas T, et al. Lessons Learned from a Double-Blind Randomised Placebo-Controlled Study with a Iota-Carrageenan Nasal Spray as Medical Device in Children with Acute Symptoms of Common Cold. BMC Complementary and Alternative Medicine. 2012;12:147. Research evaluating intranasal iota-carrageenan in children with respiratory infections.
Ludwig M, et al. Efficacy of a Carrageenan Nasal Spray in Patients with Common Cold: A Randomized Controlled Trial. Respiratory Research. 2013;14:124. Carrageenan-treated participants with confirmed viral infection experienced approximately two days faster symptom resolution in the study's per-protocol analysis.
Koenighofer M, et al. Carrageenan Nasal Spray in Virus Confirmed Common Cold: Individual Patient Data Analysis of Two Randomized Controlled Trials. Multidisciplinary Respiratory Medicine. 2014;9:57.
Eccles R, et al. Efficacy and Safety of an Antiviral Iota-Carrageenan Nasal Spray: A Randomized, Double-Blind, Placebo-Controlled Exploratory Study in Volunteers with Early Symptoms of the Common Cold. Respiratory Research. 2010;11:108. This early trial found reductions in cold symptoms and nasal viral load, although it was a small exploratory study involving 35 participants.
Read the studyClinicalTrials.gov. Iota-Carrageenan Nasal Spray in Common Cold. NCT01944631. Randomized Phase 4 trial evaluating iota-carrageenan nasal spray versus saline placebo in 200 participants.
View the clinical trialU.S. Centers for Disease Control and Prevention. Naegleria fowleri Infection: Sinus Rinsing and Prevention. CDC. The CDC specifically recommends distilled, sterile, or previously boiled water for nasal and sinus irrigation because rare fatal infections have occurred following nasal rinsing with contaminated water.