Apparently Your Nose Has A Microbiome, Too — Here's How To Keep It Healthy
When you hear the word "microbiome," you inevitably think of the trillions of bacteria—both good and bad—hanging out in your gut. After all, these busy little bugs have far-reaching effects on both physical and mental health, so it's no surprise they get all the hype.
But get this: There's not just one microbiome. Turns out, a diverse community of critters exists inside your nose, too. And while research on the "nasal microbiome" is young, some experts believe it's a pretty big deal and may play a significant role in immunity (which, of course, is something that happens to be on everyone's mind lately).
Here's the current knowledge about the nasal microbiome, how it affects health, and what you can do to support it.
First, what is the nasal microbiome?
Just as the gut microbiome refers to the collection of bacteria and other microbes that inhabit the gut, the nasal microbiome simply refers to the collection of bacteria and other microbes in the nasal passageway, or upper respiratory tract.
While it's not quite a household term yet, the nasal microbiome has started to gain attention thanks in large part to a recent study published this year in the journal Cell Reports. The gist of the research: Participants with more good bacteria in their nose tended to be at much lower risk of certain respiratory problems1—which may indicate better overall immune functioning.
For the study, researchers swabbed the noses of 100 healthy people and compared the microbes they obtained to those of patients with chronic nasal and sinus inflammation (aka chronic rhinosinusitis, or CRS). They found that Lactobacillus bacteria, which has antimicrobial and anti-inflammatory properties, was about 10 times more abundant in the noses of healthy people. This builds on previous research2 that demonstrated greater bacterial diversity in the nose and the presence of the strain Lactobacillus sakei was protective against CRS.
In a recent Instagram video, renowned neuroscientist Andrew Huberman, Ph.D., shared his excitement about the new research with his 47,000 followers, saying that in addition to promoting healthy immunity, he's willing to bet these beneficial bacteria also help promote healthy brain function due to their proximity to the brain. Of course, that's all just educated speculation for now—but it's pretty fascinating to think about.
How does the nasal microbiome play a role in immune health?
It's hard to say, exactly, but researchers have a few theories about how a healthy nasal microbiome might help support immunity. "Clinical trials in patients still have to be performed, but based on molecular research and animal models, we are exploring a triple mode of action of the selected beneficial [Lactobacillus] bacteria," says study author and microbiologist Sarah Lebeer, Ph.D. According to Lebeer, the three mechanisms by which good bacteria in the nose may boost health include:
- Antipathogenic activity: Lactobacillus seems to have selective antibacterial, antifungal, and antiviral activity toward dangerous viruses that may enter the nose.
- Barrier-enhancing activity: Much as they do in the gut, good bacteria in the nose may stimulate tight junction functioning of nasal epithelia (i.e., nasal lining) so that this barrier becomes less porous and is better protected against invading viruses and allergens.
- Overall anti-inflammatory and immune-balancing effects.
Although much more research is needed, all of these potential mechanisms suggest that a healthy nasal microbiome may act as a first line of defense, tackling viruses like the cold or flu before they can really take hold, fighting off bacteria that could lead to sinus infections, and offering protection from pollen, mold, and other allergens you may encounter when you breathe.
What could mess with your nasal microbiome?
It's not always clear, but according to Lebeer, several things that are known to negatively affect overall health also seem to harm the balance of bacteria in the nasal microbiome.
For example, in previous research involving smokers, Lebeer and her colleagues found an association with more pathogenic or harmful taxa in the nasal passageways such as Staphylococcus and Corynebacterium bacteria.
Overuse of antibiotics may have a negative impact on the nasal microbiome as well—just as it does in the gut microbiome.
There's also some reason to think that poor gut health itself—caused by poor diet, antibiotics, or any number of factors—may in turn worsen the health of your nasal microbiome and lead to problems. "My practice has shown me that the implications of an unhealthy gut microbiome influence systems all over the body, including those connected with the respiratory systems, such as allergies and asthma," says Vincent Pedre, M.D., author of Happy Gut. "But when you improve gut health, you also improve the health of the airways."
In fact, research suggests3 a significant connection between poor gut health at a young age and later development of asthma, and people with asthma have been shown to have different nasal microbiome compositions than people without.
Lebeer speculates that the gut microbiome could affect the nasal microbiome in two ways. "There could be a direct effect because the nasal and oral cavity are directly linked via the nasopharynx," says Lebeer. "There could also be an indirect link due to a gut-respiratory systemic axis [or gut-lung axis3]. This means that orally consumed prebiotic and probiotic foods could have signaling, metabolic, and immune effects in the gut that can also be transferred and observed in the nose."
How can you strengthen or support your nasal microbiome?
There's no magic bullet—although, Lebeer is in the process of developing a probiotic nasal spray containing Lactobacillus bacteria that colonize and optimally balance the nasal microbiome, which may be particularly beneficial for those suffering from CRS.
The good news: There are a few ways experts think you can positively influence your nasal microbiome in an indirect manner—and they're pretty straightforward:
- Don't smoke: Considering how smoking may increase colonization of harmful bacteria in the nasal microbiome, this one's a no-brainer.
- Pop a probiotic supplement: Research on humans and animals has shown4 that oral probiotics (containing Lactobacillus GG, Bifidobacterium, Lactobacillus acidophilus, and Streptococcus thermophilus) reduce colonization of the nose and upper respiratory tract by pathogenic bacteria like Staphylococcus aureus.
- Eat more fermented foods: According to Lebeer, fermented foods such as kimchi, sauerkraut, kefir, and yogurt have been associated with the presence of bacterial groups in the nose known to generally have beneficial functions, such as Lactobacillus.
- Take care of your gut: In addition to probiotics and fermented foods, taking any steps you can to support your gut microbiome is smart, given the likelihood that the gut microbiome may be able to influence the nasal microbiome both directly and indirectly. Think: eating more fiber-rich plant foods, exercising regularly, spending time in nature, and taking steps to curb stress.
- Be mindful of your meds: It's not totally clear if antibiotics affect the nasal microbiome, but considering their effect on the gut microbiome, it's good to be cautious. As always, try not to take antibiotics unless your doc says there are no other alternatives.
There's still so much unknown about the nasal microbiome, but—based on the current research—this collection of bacteria and other microbes lining your nasal passages may play an interesting role in protecting you against viruses, bacteria, and allergens in the environment. It might even affect brain health, as suggested by Huberman (but that research hasn't even begun yet). While there may not be an official nasal-microbiome-boosting protocol just yet, taking the steps outlined above is a great place to start.
Stephanie Eckelkamp is a writer and editor who has been working for leading health publications for the past 10 years. She received her B.S. in journalism from Syracuse University with a minor in nutrition. In addition to contributing to mindbodygreen, she has written for Women's Health, Prevention, and Health. She is also a certified holistic health coach through the Institute for Integrative Nutrition. She has a passion for natural, toxin-free living, particularly when it comes to managing issues like anxiety and chronic Lyme disease (read about how she personally overcame Lyme disease here).