How to Improve Oral Health & Its Critical Role in Brain & Body Health

The episode opens by widening what "oral health" means. Most listeners, the host says, think of tooth health, appearance and fresh breath. He argues that oral health also covers the oral microbiome, the palate, the tonsils and the whole oral cavity, and that it is an extremely important part of general bodily health. On that basis he adds a seventh pillar to the six pillars of mental health, physical health and performance that the podcast has discussed before, and he says this is not a trivial step.

He lists the existing six pillars, in no particular order: sleep; sunlight and light exposure generally, which includes dark exposure; nutrition; exercise or movement, covering both cardiovascular exercise and resistance training; stress management; and relationships and social engagement, including relationship to self. The new pillar is oral and microbiome health, which he also calls oral and gut health, because the mouth and the gut are contiguous. His reason for raising it to a pillar is that daily oral-health practices extend to cardiovascular health, metabolic health and brain health, and to staving off diseases in those parts of the body.

He then previews two claims he presents as surprising. First, teeth can fill back in cavities that have already formed, provided the cavities have not gone too deep into the tooth layers. Second, saliva is more than spit: it contains substances that let teeth rebuild their strength and that support the oral cavity, the gut microbiome and the body generally. He promises zero-cost and low-cost protocols, including some that save money, to restore, improve and maintain oral health. He also calls oral health perhaps the most overlooked aspect of mental and physical health.

I cannot overemphasize enough how much oral health influences your general bodily health.

The host frames the discussion with a self-assessment quiz. Category one is people who routinely brush at least twice a day and floss at least once a day. They may also use mouthwash, mints or gum, whiten their teeth, or see the dentist more often than the recommended twice a year. Category two is people who are more casual: they brush once a day but not regularly twice, or they brush twice but rarely floss, and they may see a dentist every six months, once a year or less often. Category three is people who care about tooth cleanliness but also about the oral microbiome, the gums, the soft and hard palate, and the links between the mouth and brain, cardiac and metabolic health.

He estimates, explicitly as his own argument, that 95% and perhaps 98% or more of people fall into category one or two. His central and counterintuitive claim is that people in category one, despite brushing, flossing, using mouthwash, whitening and rinsing after sugary meals, are probably still doing things that deplete and disrupt their oral health, because they lack current information about what oral health is. Their teeth may stay white and they may not be told they have cavities, yet their habits may be undermining other aspects of brain and bodily health.

He says the aim is not to frighten listeners. For category one, he suggests there are added practices and a few things to avoid that are likely to improve overall health quickly, at zero or low cost. For category two, he says people are probably depleting both oral and bodily health. He then adds a qualification: some people in category two, who do less hygiene, freshening and whitening, actually have a healthier overall oral microbiome. He stresses this is not always the case, though it often can be. He also notes that some acidic-food rules will be examined later as to whether they really matter for cavity formation.

On sourcing, the host says he consulted at least five dentists while preparing the episode, including a pediatric dentist, a periodontist and practitioners in the functional dentistry category. He describes the content as the overlap of what they agreed on, and says he will point out some differences between them. He reports being positively surprised by how much consensus there was on best protocols for tooth and oral health.

Before the protocols, the host lays out basic anatomy, promising to keep it functional rather than a list of names. Teeth, like most body structures, are layered: cells are born in one place, migrate and form stacks of different cell types. The outer layer is enamel, which he says is not white but translucent, letting light through while remaining somewhat opaque. Beneath it is dentin. Cavities form from the outside in, as holes that bacteria burrow through the enamel and, in unlucky cases, into the dentin.

He states that he did not know, until researching the episode and talking to experts, that cavities that have started to form can be repaired. The mouth's chemistry, mainly how acidic or basic it is, with some mechanical factors, keeps teeth in either demineralization or remineralization. Following a dentistry convention, he shortens these to "demin" and "remin." Remineralization adds new minerals that form strong, organized crystal lattices, mainly in the enamel and to some extent in the dentin. He compares the structure to a well-formed building, while noting that some crystals are weaker.

Your teeth are always in a state of either demin or remin.

He adds that the state is one or the other, not both at once, and depends largely on the mouth's pH. The pH in turn depends largely on how much saliva is produced and on the mineral content of that saliva. The practical limit he gives is depth. Remineralization can fill in cavities that have gone into the enamel but not yet into the dentin. If demineralization has reached the deeper dentin, the tooth will most often need to be drilled and filled. He also says that, typically but not always, a person's cavities tend to be at a similar depth across the mouth, which he calls good news if none has reached the dentin.

He gives a personal reason for caring about avoiding drilling. As a child, his adult teeth came in behind his baby teeth, so all his baby teeth had to be pulled and he had many Novocaine injections. Because he hated syringes in his mouth, he chose to have cavities drilled without Novocaine. He jokes that he may have bitten a dentist or two, but says he now thinks dentists and regular cleanings are wonderful, and he says frequency of cleanings will be discussed later. He also repeats the cynical phrase "Drill, fill, and bill" to note that someone, or their insurance, is charged for fillings.

The gums, or gingiva, are described as more than soft tissue. The host says they are very important for fixing the teeth to the bone, alongside the roots in the jawbone and a small ligament between gums and teeth that sits deeper. Most importantly for his argument, the gums form a seal around each tooth, a barrier between the oral cavity and the deeper bone and general bloodstream. That, he explains, is why dentists use a pick to check how deep the gum pockets are.

He then compares the mouth with the body's other openings. The anal sphincter stays shut. The nasal passages have mucus, the cribriform plate and bone separating them from the olfactory bulb and brain. The eyes have a blink reflex and an ocular microbiome. The mouth, by contrast, is a large opening used to eat, speak and breathe, so it takes in bacteria from the outside environment all day. Being warm, moist and full of bacteria, he says, makes it like a Petri dish.

Dryness is flagged as a major threat. He previews a later point that nasal breathing at night matters both for staving off sleep apnea and because a dry mouth can seriously disrupt oral health. He says dryness is one of the leading causes of tooth decay in people such as methamphetamine addicts, and that mouth breathers' oral health is severely depleted.

Against this vulnerability, he describes the mouth's defenses. If the pH is right, harmful organisms are killed off, and beneficial bacteria proliferate and support the sealing of the gums against the teeth, as well as tooth, tongue and palate health. The main way the cavity stays resilient, he says, is by keeping saliva healthy, though he notes other ways exist. As further evidence that something special happens in the mouth, he points out that skin cuts in people around 25 or older usually leave some scar, while cuts and burns in the mouth, with rare exceptions, heal with nearly zero scarring.

He ties these threads into a chain: treating the mouth well encourages remineralization; this works through healthy saliva; and healthy saliva depends on supporting the right bacteria while eliminating or at least limiting unwanted ones. The same practices, he says, also support gum health.