
Dr Deepa, Principal Dentist for leading London dental practice, Whites Dental.
When we think of good oral hygiene, toothbrushes, mouthwash and floss automatically spring to mind. But what if a healthy smile was just as much about your gut health as it is your gums?
Recent research into the oral-gut axis – a bidirectional communication pathway between the microbiomes in the mouth and the gut – suggests that gut health may be key to stronger teeth and brighter smiles. The link between the gut and oral health is established through several different bodily pathways, including the bloodstream, saliva and even the gut-brain axis (or link between the brain and the gut), which connects the central nervous system to digestion.
Imbalances in gut bacteria can thus contribute to oral health directly, leading to issues like gum disease, tooth decay and acid reflux, which wears away tooth enamel. Understanding the connection between what we eat and how we brush is therefore vital to both dental care and overall wellbeing.
A two-way street
As opposite ends of the digestive system, your mouth and gut are both connected parts of the same system, sharing bacteria that work together – or against one another – to maintain balance. Whilst bad bacteria can wreak havoc on your teeth and gums, good bacteria play a protective role, with probiotic strains in particular releasing acids that keep harmful bacteria at bay. This reduces the risk of both tooth decay and gum inflammation, which has been proven to increase the chance of degenerative conditions like Alzheimer’s later in life.
Indeed, it’s not just poor gut health that damages teeth. Poor oral hygiene can have a negative impact on overall physical health, as well. Research from the University of Michigan and Dental School highlights the strong link between poor oral hygiene, gum swelling and gut-related conditions like inflammatory bowel disease (IBD), ulcerative colitis and Chron’s. A 2016 study by Monserrat et al furthermore associated periodontal disease with 57 non-communicable diseases, including diabetes, cardiovascular disease and rheumatoid arthritis. These findings underscore the importance of taking care of oral hygiene in ways that extend beyond the mouth.
The role of diet
Diet is the one big thing, beyond brushing, that we can do to protect the oral and gut microbiome. Processed foods, refined sugars and additives all disrupt the balance of beneficial bacteria in our bodies, reducing microbial diversity and allowing harmful strains to flourish. Contrary to popular belief, sugar doesn’t harm teeth directly, but it does reduce the diversity of the oral microbiome, creating conditions for decay.
Simple changes in dietary habits can help things to improve. For instance, consuming foods that are rich in prebiotics, like onions, chicory root and leafy greens helps to feed your beneficial bacteria, with fermented foods like kimchi, yogurt and sauerkraut introducing plenty of prebiotics that promote balance in the gut. The word balance here is key, however, with certain fermented foods having the capacity to erode tooth enamel if consumed in excess, making moderation crucial.
Chewing food properly also helps, as the mechanical action of grinding teeth together initiates the process of breaking down food in the mouth. This once again boosts beneficial bacteria, kickstarting digestion. Eating seasonally and locally, avoiding processed foods and increasing fibre intake further support a thriving microbiome.
Rethinking dental hygiene
Whilst essential, brushing, flossing and using antibacterial mouthwash are not enough on their own. In fact, excessive use of antibacterial mouthwash can kill off both harmful and friendly bacteria, potentially exacerbating problems in oral health. The goal must instead be to nurture a diverse and thriving microbiome both in the gut and in the mouth – and this means prioritising good bacteria through foods and avoiding practices like excessive mouthwash, which indiscriminately wipe out microbial populations.
Regular dental check-ups are, of course, still essential – but these must be complemented by an overall focus on gut health and wellbeing.
A holistic approach to oral health
With approximately 20 billion bacteria in the mouth at any given time – and 750 recognised bacterial taxa – the ecosystem within our mouths is vast and complex. Managing this ecosystem requires a diet rich in fibre, prebiotics and probiotics, alongside mindful oral hygiene practices that support the interconnected microbiomes of the mouth and the gut.
The brightest smiles really do start from within – and by focussing on gut health, we can revolutionise how we care for our teeth and our gums. A diet rooted in natural, unprocessed foods, reduced sugar and an emphasis on microbial diversity can do much more for oral health than an overly harsh mouthwash and, as our understanding of the oral-gut axis grows, we will become even more adept at fostering microbial diversity, resilience and balance.
