The Science of Clearer Sinuses

The sinus microbiome is the community of microorganisms living in the nasal cavity and (paranasal) sinuses. It includes bacteria, fungi, and viruses, as well as their genes and the molecules they produce.

Healthy sinuses are not sterile. Many studies found diverse microbial communities in both persons with chronic sinusitis and healthy individuals without chronic rhinosinusitis. Each person's microbial community is a composition of microbes which can vary over time. The types and numbers of microbes (diversity and abundance), and their function play a role in sinus health and sickness. 

Researchers study the sinus microbiome because persistent inflammation generally results in changes in the composition of the microbial community. These changes include reduced diversity or an increased abundance of particular organisms (e.g., fewer Lactobacillus species and more S. aureus). This results in an imbalance or dysbiosis in the microbial community. Inflammation, medication use (antibiotics), a person’s anatomy, environment, and microbial shifts can all influence one another.

At present, the sinus microbiome field is very promising, but much is still unknown. 

 There is no single sinus microbiome (microbial composition) that defines a “healthy” sinus microbiome.

A healthy sinus microbiome is an ecosystem in balance, rather than a list of “good” bacteria. Microbes that are viewed as potentially harmful coexist with microbes viewed as good or beneficial. The exact composition of microbes varies among healthy individuals and also across different sites within the upper airway and sinuses. 

Studies find that microbes can be different in the same person depending on the location sampled - nasal passages, middle-meatus, and the sinuses. Also, sequencing methods can detect microbial DNA even when an organism is no longer alive. 
For these reasons, recent research finds that consumer microbiome test results are flawed and unreliable, and any results should be interpreted cautiously. 

Dysbiosis is a general term for a microbial ecosystem that has shifted away from a stable, health-associated state. It is imbalanced. In the sinuses, this involves loss of microbial diversity, depletion of potentially protective microbes, or too many of other microbes.

Many studies report differences between the sinonasal microbiomes of people with chronic rhinosinusitis and those of healthy comparison groups. Findings have included community “collapse", reduced diversity, and increased numbers of some bacteria, such as S. aureus in some patient groups. Some Lactobacillus species, including L. sakei, is reduced or depleted in those with chronic sinusitis. 

The sinus microbiome is in an environment that is always changing. Respiratory infections, inflammation, allergies, antibiotic exposure, corticosteroid treatment, surgery, impaired mucus clearance, environmental exposures (e.g., wildfire smoke, cigarette smoke), and differences in sinus anatomy may all influence or disrupt that environment. Age, geography, season, household contacts, and other personal factors may also contribute. 

Antibiotics inhibit or kill bacteria. When medically necessary, they can be important treatments for bacterial infections, but they are known to also effect beneficial organisms and change the sinus microbial community.

A disturbance in the microbiome does not automatically produce illness. Problems may be more likely when a disturbance coincides with persistent inflammation, altered mucus flow, a weakened epithelial barrier, or repeated exposures (e.g., repeated infections, repeated courses of antibiotics). 

Latilactobacillus sakei—still commonly called Lactobacillus sakei—is a species of lactic acid bacterium. It is best known from food fermentation and has been isolated from fermented vegetables, meat, and fish. Different strains can have different properties, so findings about one strain do not automatically apply to every L. sakei product.

Interest in L. sakei and sinus health grew from a 2012 study that compared sinus microbial communities associated with chronic rhinosinusitis and healthy controls. In a mouse model, L. sakei helped protect against epithelial and inflammatory effects from another bacterium. This was influential proof-of-concept research. Further research found that L. sakei is a keystone bacteria found in healthy sinuses, but is depleted or absent in those with chronic sinusitis.

Laboratory and food-science research shows that some L. sakei strains (such as the one used in Lanto Sinus) are especially effective against harmful bacteria.

The strain of L. sakei used in Lanto Sinus (L.sakei ProBio65) is especially effective in competing with other microbes, dominating over some pathogenic bacteria species (e.g., S. aureus), and producing antimicrobial compounds. This is why several studies are studying L. sakei (using Lanto Sinus) in people with chronic sinusitis.

Researchers published a study of Lanto Sinus in people with hard-to-manage chronic rhinosinusitis, and a larger promising follow-up study is under way. Building on the results from their first study, they are now studying Lanto Sinus on a larger group of persons with chronic rhinosinusitis. Another ongoing study being conducted through the University of Illinois Chicago is using Lanto Sinus in nasal irrigations in persons with chronic rhinosinusitis. 

Beneficial bacteria may support a microbial ecosystem through several mechanisms, such as dominating over some bacteria (e.g., S. aureus) or communicating with immune cells. In a well-functioning ecosystem, these activities help resist excessive expansion of potentially harmful organisms—a property known as colonization resistance.

Lanto Sinus supplies live L. sakei intended to support sinus microbiome balance.

The sinus microbiome and what effect probiotics have on chronic rhinosinusitis are an active area of research, but much is still unknown. At this time only a few well-controlled human trials are testing or have tested probiotic strains specifically for sinonasal outcomes.

Chronic rhinosinusitis with nasal polyps differs from disease without polyps. Allergic inflammation, asthma, dental disease, immune conditions, anatomy, and prior surgery can all shape symptoms and treatment responses. Thus, microbiome interventions are unlikely to have the same effect on every person.

Probiotic products are not interchangeable and vary according to strain, dose, formulation, storage conditions, and route of use. Most oral probiotics contain species selected for gastrointestinal use, not the sinuses. How it is used matters because a swallowed probiotic first encounters the digestive tract, while a product used in the nose and mouth is intended to interact with the surface of the upper-airways.

Lanto Sinus contains live L. sakei (which is found in healthy sinuses). It is formulated as a freeze-dried powder for use by the nose and mouth, which can be used several ways (in the nostrils, swished in the mouth, or added to a properly prepared saline sinus rinse). It is a refrigerated probiotic supplement designed to balance the sinus microbiome.

Laboratory studies show the L. sakei strain in Lanto Sinus (ProBio65) competes well against other bacteria, including S. aureus.

Use Lanto Sinus as needed to support your sinus health, and stop when you feel well.

Since Lanto Sinus is a probiotic, it differs from other sinus products (e.g., saline rinses, nasal corticosteroids, antibiotics) which have different actions and medical indications.

Studies report that Lactobacillus sakei is found throughout the world. Currently there are over 230 known strains of Lactobacillus sakei, which were collected from meat, seafood, and vegetables. It was originally isolated years ago from sake or rice wine - thus the name Lactobacillus sakei. Studies from Korea have found it during fermentation in most brands of Korean kimchi.

Lactobacillus sakei is considered antibacterial, bacteriostatic, and bactericidal against many species of bacteria (Zagorec & Champomier-Verges, 2017). Antibacterial means destructive to or killing bacteria or suppressing their growth, bacteriostatic means that it prevents the growth and reproduction of bacteria, and bactericidal means it kills bacteria. The food industry has studied and used L. sakei (e.g. as a sausage culture starter) because of its value against pathogens such as Listeria.

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