Is there more than one microbiome?

When we think of the human microbiome, we typically think of the gut microbiome in the lower gastrointestinal tract. However, thanks to many years of research, we have discovered many unique microbiomes throughout the body, such as the mouth, the urogenital tract, and even the skin. Each of these microbiomes exists to serve the body by providing a protective health benefit for their specific location and are considered to be well-balanced when the beneficial bacteria effectively compete with pathogenic bacteria. Additionally, our microbiomes exist to provide support to the immune system by decreasing inflammation from elevated cytokines.[1]

As science continues to explore the various microbiomes throughout the human body, the oral microbiome, in particular, has fascinated researchers. Besides being the second-largest microbiome (after the gut), the oral microbiome presents an incredibly biodiverse collection of microorganisms. With the advancement of genomic technologies, we can learn even more about the importance of this complex microbiome and its significant implications for our health.[2]  A healthy oral microbiome is a key component of our overall health. To understand how to properly support the oral microbiome, let us first examine its uniqueness in relation to the rest of the body.

How is the oral microbiome unique?

The primary uniqueness of the oral microbiome is its diversity. This microbiome features a vast array of bacteria, viruses, yeast, archaea (species of methanogen producers), and protozoa. There are more than 1,000 species of bacteria within the oral microbiome. Though this microbiome includes some familiar groups such as actinobacteria, bacteroides, and firmicutes, many species remain unidentified.[8] These groups include the commonly known lactobacillus, bifidobacteria, and streptococcus bacteria. These beneficial probiotic bacteria work to keep the oral biofilm healthy and balanced. The balance of the microbiome acts as a preventative measure against the overgrowth of pathogenic bacteria.

An imbalance of beneficial bacteria and pathogenic bacteria, as well as environmental factors (such as diet and smoking) can cause dysbiosis, which leads to a broad array of dental health complications.

How does a healthy oral microbiome contribute to healthy teeth and gums?

Because there is a delicate balance of probiotic and pathogenic microbiota within the oral cavity, even a slight change in diet can have profound health implications. One such example is the bacteria Streptococcus mutans. S. mutans is a typical inhabitant of the oral microbiome and does not necessarily pose a threat when the microbiome is healthy and balanced. However, under certain conditions and when the amount of S. mutans becomes excessive, it is the most common bacteria contributing to periodontal and dental caries. S. mutans and other bacteria form biofilms on the teeth, commonly known as dental plaque.[11] The bacteria within the biofilm metabolize sugars and produce acids that break down or demineralize tooth enamel and dentin, leading to dental caries. Therefore, a person’s diet, specifically the amount of sugar in their diet, can create an environment where pathogenic bacteria thrive, causing an imbalanced microbiome and increasing the risk of developing dental caries. Supporting a healthy oral microbiome goes beyond a healthy mouth, research has found significant correlations between dental health and systemic health.

Are there supplements that support the oral microbiome?

Research has demonstrated clear indications that a healthy oral microbiome supports over all health. One method of supporting the oral microbiome is supplementation with probiotics. Research has shown improved oral microbiome health when supplementing with various probiotics. For example, oral tablets containing Lactobacillus salivarius have been shown in clinical studies to improve the balance of the oral microbiome.[20] Furthermore, when EGCG (of the form found in green tea), which is an antioxidant, was administered alongside L. salivarius, the beneficial effect was even more substantial. Lactobacillus reuteri, also a probiotic strain of bacteria, produces organic acids, hydrogen peroxide, and a bacteriocin-like compound that support microbial balance.[22] As with L. salivarius, the use of oral tablets containing L. reuteri, were found to provide tangible benefits.[23] Indeed, based on this cited research, oral tablets appear to be an extremely effective way to target and support a healthy oral microbiome.

Conclusion

Because the human body relies on beneficial bacteria to maintain proper health and functioning of our microbiomes, their may be benefits to supporting these essential organisms. In the case of the oral microbiome, research suggests that specific probiotic supplements may play a role in maintaining a healthy microbial balance.  Because the oral microbiome plays a crucial role in the health of the entire body, supporting a healthy oral microbiome may also support broader systemic health.

References

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