I want to share something I was never taught in dental school, but I wish I had been.
It would’ve changed how I practiced from day one, and it might change how you think about your own health.
Your mouth isn’t dirty—it’s alive.
I was trained to treat the mouth like a battlefield. Kill the bacteria. Disinfect. Fill the holes.
That was wrong.
Your mouth is an ecosystem. It’s in constant dialogue with your blood, your gut, even your brain. If your gums bleed—even a little—that’s a doorway to every other system in the body where bacteria can now enter and cause major problems.
A few examples of this…
Fusobacterium nucleatum has been found in colorectal tumors.
Porphyromonas gingivalis has been detected in brains with Alzheimer’s.
People with gum disease are more likely to have inflammatory bowel disease.
In this newsletter, I hope to convince you—whether you’re a patient, doctor, or hygienist—that dentistry has been wrong all these years, and what we need to do instead.
First things first…
I’m begging you to stop carpet bombing your mouth!
Remember those TV ads showing blue liquid swirling through the mouth killing everything in its path?
Now we know better. Mouthwash (even the “natural” ones made with essential oils)…
- lowers microbial diversity
- acidifies saliva
- wipes out nitrate-reducing bacteria
- suppresses nitric oxide production
And nitric oxide, by the way, is how your body keeps blood vessels relaxed. It helps regulate blood pressure, supports athletic performance, and yes—even affects sexual function!
One study showed beet juice lowered blood pressure in older adults—unless they’d been rinsing with antiseptic mouthwash. Then the effect disappeared.
So if you’re working on blood pressure, sleep apnea, or recovery, ditching the daily mouthwash routine might be one of the easiest changes you can make.
Your mouth and your gut are connected
You swallow about 1.5 liters of saliva every day. Along with it, oral microbes. Many die in the stomach. Some survive. And when your gums are inflamed, even more microbes get direct access to the bloodstream.
Research shows oral bacteria like Klebsiella and Fusobacterium can colonize the gut and drive inflammation. In people with IBD, they’ve been found sitting in inflamed regions of the intestine. In animal studies, gum disease pathogens actually worsened colitis.
It’s called the oral–gut axis, and it means your gum health can influence how your gut behaves.
A dead simple tool: green tea
I’m constantly asked what to use instead of mouthwash. You might be surprised by my answer: A glass of green tea (link to the one I drink every day) does more for your oral ecosystem than any “advanced” rinse can.
Polyphenols in green tea:
- Make it harder for cavity-causing bacteria to stick
- Block gum disease bacteria from latching on
- Thin biofilm without nuking the good guys
- Cut bad breath compounds
- Support nitrate-reducing bacteria that feed nitric oxide
Sugar is still part of the story—you already know too much of it feeds cavity-causing bacteria.
But I’m afraid us dentists (sorry!) have focused too much on AVOIDING sugar, and haven’t placed enough emphasis on what TO eat!
What matters just as much are the foods that build resilience: the ones that strengthen enamel, keep your gums calm, and feed the bacteria that protect you.
- Nitrate-rich plants: arugula, beets, spinach, celery
- Fermented foods: yogurt, kefir, kimchi, miso
- Polyphenols: berries, cacao, cranberries, pomegranate
These don’t just help your teeth. They influence your gums, your gut, your brain, and your vascular system, thanks to this oral-gut axis.
What I do at home:
- Tongue scrape
- Rinse with warm saltwater, MCT or coconut oil (also called oil pulling) or just good old plain water!)
- By the way – it’s better not to rinse right after brushing with nano-hydroxyapatite toothpaste. You want the nano-HAP to have a chance to sit on teeth to work.)
- Brush with nano-hydroxyapatite
- Green tea (this one) in between meals to help restore pH
- Nasal breathing, day and night: keeps saliva steady and the oral ecosystem balanced
- Eat tons of fermented foods (I’m a big sauerkraut fan)
- Targeted oral probiotics: certain S. salivarius strains help with bad breath and gingival health (I recommend and take these ones)
- I love making my “oral microbiome omelette” for breakfast (recipe here)
If you’re unsure what’s happening in your own mouth, there are salivary oral microbiome tests (link to the one I recommend) that can show whether nitrate-reducers are present, or if troublemakers like P. gingivalis are overabundant.
Why go through all the trouble to “fix” your oral microbiome?
- Lower blood pressure without another pill
- Better sleep and fewer apnea events
- Fresher breath
- Protection for pregnancy, cognition, and metabolic health
- Stronger teeth and gums as you age
P.S. Know someone who needs an oral microbiome reset? Forward this to them — they never have to miss another newsletter if they sign up for future emails here.
The post What I Wish Dental School Had Taught Me About the Oral Microbiome appeared first on Ask the Dentist.
