The Mouth-Mind Connection: How Oral Health Influences Brain Health

As we enter the month of March, I thought it would be essential to focus on the most vital organ (of course, all of them are vital!) in our bodies–our brains.

The mind and the mouth are more connected than you might have thought, but hey, they are only a few inches away from one another. As we’ve talked about with previous diseases and conditions, our oral health is directly connected (through all those annoying bacteria) to the overall health of our bodies. And in the case of our brains, this means the bacteria in our mouths can significantly contribute to one of the most devastating diseases, dementia.

Better oral health equals less bacteria, which equals better brain health. I know, easier said than done. But the importance of maintaining our minds is non-negotiable!

So, let’s get into the connection between oral health and brain health, and most importantly how to prevent disease.

The Mouth-Brain Connection

Let’s start by diving into HOW your mouth affects brain health. Of course, we are talking about our not-so-good-friends bacteria Pg and Fn. How bad are these bacteria? A recent study has actually shown that deaths caused by and diagnosis of Alzheimer’s in patients sixty-five and older were associated with antibodies of oral Pg as well as the presence of periodontal disease before dementia. This means oral bacteria is no joke!

While bacteria is the main contributor, lifestyle, diet, and oral habits can all be contributors to poor oral health. You see, not only do oral infections spread to the rest of the body, eventually leading to the brain, but the deterioration and tooth loss derived from gum disease creates poor chewing ability that leads to nutritional deficiencies, which aid the progression of dementia. This, in turn, creates greater cognitive decline, which exacerbates all the aforementioned complications - the cycle continues.

The Big 3

What is dementia, really? Dementia is an all-encompassing term that labels the cognitive decline associated with damaged neurons (brain nerves) and their connections in our brains. Unfortunately, many of us have witnessed a loved one with those all-too-familiar symptoms of a failing memory and personality changes. It’s more than just having a bad memory or forgetting things easily; dementia truly affects and damages cognitive function.

The three main varieties of dementia are Alzheimer’s, vascular dementia, and Parkinson’s.

Alzheimer's, accounting for 70 percent of all dementia cases, is typically acquired from a lifetime neural inflammation, which can be caused by a bacterial infection, poor blood sugar control, or even viruses. However, there are a number of gene mutations, like ApoE4 (made popular by Chris Hemsworth) that can also lead to an increased risk of early-onset Alzheimer’s.

To really understand Alzheimer’s, we need to understand the blood-brain barrier. The BBB is a semi permeable membrane that allows certain substances into the brain (think glucose, oxygen, anti-anxiety medications, caffeine, alcohol) to affect the brain and keeps harmful materials out (bacteria, viruses, fungi). Our brains also need cholesterol in order for our neurons to function properly and the brain can synthesize its own cholesterol in addition to what is transported in. The blood-brain barrier can be broken down by bacteria, stress, inflammation, diseases, smoking, and having the ApoE4 mutation (which is responsible for cholesterol transport in the brain). A leaky blood-brain barrier disrupts the brain’s ability to protect its local cholesterol and structures and can therefore lead to neurodegenerative diseases.

Vascular dementia is often caused by a reduction of blood flow to the brain, usually as a result of obstructive sleep apnea, chronic inflammation of blood vessels, smoking, high blood pressure, being overweight, and having diabetes (dementia is often considered the “diabetes of the brain”). In particular, these patients may experience more problem-solving issues over general memory loss.

The final major type of dementia is a result of Parkinson’s disease. Scientists are still unsure what causes it, but whatever the origin, Parkinson’s disease occurs when the nerve cells become damaged or die off, which decreases dopamine in the brain (dopamine smooths our muscle functions). A classic symptom of Parkinson’s is seeing someone with a tremor. Due to their poor motor function, Parkinson’s patients often also develop poorer and poorer oral hygiene as the disease develops, which further exacerbates the issue as oral bacteria causes neural inflammation.

Why are the elderly most affected?

As a patient’s cognitive ability declines, so does their oral hygiene, causing more bacteria to

invade, which progresses dementia even further, and so on and so on...Now we have compounding effects atop compounding effects. Starting to get the picture?

So, let’s talk about the main reasons that dementia patients are primarily older.

Reason #1: the older someone is, the more likely they are to have an oral or systemic disease, which we now know is related to dementia.

Reason #2: the elderly are the most likely to be missing teeth, whether that be from prolonged gum disease, cavities, or infections, or just having lived longer and experienced more accidents and wear and tear. Missing teeth leads to digestive and nutritional problems which will affect brain health.

Reason #3: the elderly often experience a loss in community and social interactions which is critical to maintaining cognitive function and health span.

Researchers have found that adults with missing teeth are 48 percent more likely to develop cognitive impairment and 28 percent more likely to develop dementia. Why? If you’re unable to chew healthy, nutritious foods it’s easy to turn to high-carb processed snacks that are easier to swallow. This leads to a spike in blood glucose levels, hence the condition, “diabetes of the brain.” No nutrients mean more inflammation!

So, What Can We Do?

Here’s the good news–1/3 of all Alzheimer’s cases are preventable just by keeping Pg and Fn bacteria and blood glucose low. But this doesn’t mean you can skimp on your oral hygiene routine. Taking care of your brain health starts at home with the simple act of brushing your teeth–or helping an elderly parent brush theirs. Just by brushing regularly you can eliminate those blood-surfing bacteria (Pg and Fn) that could infiltrate your brain.

Flossing–I know we all drag our feet to do it–needs to be a big part of your daily routine. Then add mouthwash (alcohol-free!) on top and you’ve hit the oral health trifecta. You can’t go wrong.

On top of your at-home routine, you need to see your dentist at the very minimum twice a year…but I really suggest upping the frequency of your visits.

As a dentist, I’ve seen firsthand how tooth decay and tooth loss can put you in the grave expeditiously. Now, I advise my elderly patients to keep their teeth at all costs. If you want to live a long and healthy life, mind your teeth! I know, I’m a dentist, and of course I’d say that. But there is a direct correlation between the number of teeth you retain, and the average number of years lived. Studies clearly show a 4 percent increase in the five-year survival rate per additional tooth retained at the age of seventy. The tipping point for survival is keeping at least twenty teeth. This means taking proper care of your teeth can actually SAVE your life.

This doesn’t have to happen to you! Awareness is the first step. And there are tools that can help. Your dentist can help to get you on a daily oral hygiene routine and identify signs of oral bacteria that could impact your brain health. Good oral health means good brain health. Our brains need to be protected at all costs, so start with the simple and easy steps to keep your mouth and teeth (and I mean keeping most of your teeth as you age) healthy for years to come.

Want to know more about the connection between oral health and brain health? Then grab a copy of Saved By the Mouth or schedule a Telehealth appointment today.