Our digestive system (and our mouth belongs to it)  contains trillions of bacteria, viruses, fungi, and other microorganisms, that coexist in a delicate balance to regulate everything from your mental health to your skin’s sensitivity. If something happens to disturb this balance, for example, you take a course of antibiotics, you may experience symptoms ranging from digestive issues to psoriasis. The shift to more pathogenic flora causes tooth decay or caries. Oral streptococci, such as Streptococcus mutans and Streptococcus sorbrinus, are considered to be the main etiological agents of tooth decay in children. Other bacteria, such as Prevotella spp. and Lactobacillus spp., and fungus, that is, Candida albicans, are also related to the development and progression of early child caries.

That’s why fermented foods ( like kimchi, sauerkraut, and kefir ) that are rich in probiotic bacteria get such high marks in health circles. Your mouth, as I have mentioned before, is the entry point to your gut, and contains a similar community of important organisms that help to regulate your whole body.


Of course, we are all aware of the need to maintain good dental hygiene. What is changing about that now is twofold. One, we are understanding more about how the microbiome can impact things inside and outside our mouths. And two, the idea of “clean at all costs”  is changing.  Bad breath and cavities are signs of an unbalanced gut microbiome. It is a chicken-or-egg situation. They go hand in hand and one can facilitate the other. Some infections in other parts of your body tend to coexist with bacterial imbalances in the mouth. Some ear infections, as well as gum disease, and some infections in the throat can be a sign of problems with the oral microbiome.


Keeping balance in the microbiome isn’t just about elimination bad bacteria, however. It’s also about letting good bacteria thrive, which brings us to public-health-enemy No.1 for doctors of different specialties: mouthwashes with alcohol and sodium lauryl sulfate (SLS). These ingredients absolutely blast your mouth and give you this intense feeling of cleanliness. But it is ephemeral. If you checked the bacterial balance in your mouth about an hour later, it would be skewed towards the bad bacteria.  A better way to care for your oral microbiome is to keep your tongue clean. The tongue is like a rug, bacteria get into the grooves and stay there under anaerobic (no oxygen) condition. Diet also makes a big difference: the healthier, more versatile and lower in sugar the diet is, the easier it will be to maintain a healthy oral microbiome.