The Mouth-Mind Connection: How Oral Health Influences Brain Health: Part 1

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 of 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.

Stay tuned for next week’s blog: The Mouth-Mind Connection: How Oral Health Influences Brain Health: Part 2, where we will explore who is most affected by dementia and what we can do to prevent it.

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.

To learn more, please visit Dr. Katie Lee’s page on our Protocol Directory.

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Katie Lee DDS