🦷 I Kept Seeing This Weird Symptom in My Patients—Until I Finally Figured Out Why

When I first started practicing dentistry, I kept noticing the same frustrating pattern in my patients. They brushed, they flossed, they did “everything right.” And yet—they still had cavities, bleeding gums, and bad breath.

At first, I blamed diet. Maybe sugar was the issue? But then I looked closer.

The real problem? They were mouth breathing at night. I didn’t have a name for it back then, but I was seeing oral microbiome dysbiosis in real-time—before it was even a recognized condition.

My patients who breathed through their mouths at night had:
✔ Red, inflamed gums that bled easily
✔ Persistent bad breath, no matter how much they brushed
✔ More cavities—even with great hygiene
✔ Frequent canker sores and oral irritation

Now, decades later, science has finally caught up. Mouth breathing dries out your mouth, wrecks your oral microbiome, and leads to all of these issues.

💡 Want to know if this is happening to you? Try this simple test tonight: Tape your mouth shut with Nexcare tape (the one I use is linked on my website, but use whatever makes you most comfortable). If the tape stays on all night and you wake up feeling refreshed, your nasal breathing is probably fine. If the tape comes off, or you wake up with dry mouth, bad breath, or sensitive teeth after your morning coffee—that’s a red flag. You might have an airway issue (like nasal obstruction or sleep apnea) that needs further investigation.

🚨 Important Note: Mouth taping isn’t for everyone. If you have chronic nasal congestion, a deviated septum, or sleep apnea, focus on improving nasal breathing before trying mouth taping. If you struggle with mouth taping, don’t ignore it—it’s a sign to look deeper into your breathing.

📖 Want to dive deeper? I cover this in detail in my book, The 8-Hour Sleep Paradox, which explains how undiagnosed sleep-disordered breathing affects everything from energy levels to brain health.

Why Mouth Breathing Wrecks Your Teeth
A happy tooth is a tooth that’s bathed in saliva.

Saliva isn’t just moisture—it’s your body’s natural defense system for your mouth.

It plays a critical role in keeping your teeth strong and cavity-free by:
✅ Washing away harmful bacteria that cause decay and gum disease ✅ Neutralizing acids that erode enamel
✅ Delivering essential minerals (like calcium, phosphate, and magnesium) to remineralize your teeth (one of many reasons I take this magnesium supplement every day)
✅ Supporting your immune system by containing antimicrobial proteins that fight off harmful bacteria

Every time you eat, your teeth go through a demineralization cycle—acidic exposure that temporarily weakens enamel.

When you’re constantly snacking, your teeth never get a break.

The only way to reverse the damage is through remineralization, which can’t happen without saliva.

If your mouth is dry—whether from mouth breathing, dehydration, or medication—you’re missing out on your body’s built-in repair system.

Why Saliva is Everything for Your Teeth & Health
Without saliva, your teeth would literally crumble.

It’s 95% water, but don’t let that fool you—saliva is packed with enzymes, minerals, immune defenses, and even digestive properties that:
✔️ Keep your mouth’s pH balanced (unhealthy saliva = more cavities)
✔️ Prevent oral dysbiosis (aka bad bacteria taking over)
✔️ Break down food and protect your gut from harmful microbes
✔️ Even help lubricate your airway—which is why mouth breathers are more likely to snore and have sleep apnea

Every day, you swallow 1.5 liters of saliva—and with it, about 140+ billion bacteria that go directly to your gut. If your saliva is off, your entire microbiome suffers—leading to gut issues, inflammation, and even skin problems like acne.

How to Protect Your Teeth from Mouth Breathing
1️⃣ Mouth Taping at Night – The easiest way to retrain yourself to breathe through your nose is to tape your mouth shut while you sleep. Many people notice better sleep, no more dry mouth, and even clearer thinking after doing this. If you’re congested or have a cold, try sleeping propped up at an angle—this keeps your nasal passages more open and makes it easier to breathe through your nose.

💡 But here’s why mouth taping is also a powerful diagnostic tool: If the tape stays on all night and you wake up feeling great, that’s a good sign your nasal breathing is working well. But if the tape comes off, or you feel panicked or short of breath, that’s a red flag—you may have an underlying airway issue (like nasal obstruction or sleep apnea) that needs further investigation.

This is why I use mouth taping as a first-line differential diagnosis before recommending sleep studies or interventions. It’s a simple way to gather information about your airway health before taking the next step.

And personally, I never go to bed without mouth tape. Nor does my wife. We’re great nasal breathers, but the mouth tape ensures our lips don’t fall open while asleep. Our Oura ring scores show the difference when we mouth tape versus when we don’t.

2️⃣ Magnesium for Saliva & Recovery – Since saliva quality depends on mineral content, getting enough magnesium is essential. Magnesium helps activate enzymes in saliva that maintain its protective qualities and allows for proper remineralization of your teeth. Without enough magnesium, your saliva can’t effectively deposit calcium and phosphate into your enamel, leaving your teeth vulnerable to cavities. Since magnesium plays such a key role in saliva quality and overall recovery, I take one with all seven essential forms.

3️⃣ Intermittent Fasting for Oral Health – Most people think of fasting as a gut or metabolic hack, but it turns out it’s just as important for oral health. Every time you eat, your teeth go through a demineralization cycle—acid exposure that temporarily weakens enamel.

If you’re constantly snacking, your teeth never get a break. But when you space out meals or practice fasting, your saliva has uninterrupted time to remineralize and strengthen your enamel.

For my patients who struggle with cavities despite great hygiene, simply eliminating snacks between meals has been a game-changer. Aim for three high-quality, protein-rich meals per day instead of grazing.

That said, fasting isn’t for everyone—some studies suggest it may have drawbacks. But if you do fast, skipping dinner is ideal. Eating earlier in the day supports better sleep, stabilizes blood sugar, and aligns with your body’s circadian rhythm.

4️⃣ Brushing Before, Not After, Coffee or Acidic Drinks – Brushing immediately after acidic drinks like coffee can wear away enamel. Instead, brush first thing in the morning, then wait at least 45 minutes before brushing again. If you want to minimize acid damage, rinse with water or swish with green tea to neutralize pH before brushing.

5️⃣ Rebuilding the Oral Microbiome & Gut Health – Since taking this probiotic, I’ve noticed my breath stays fresher overnight, and I wake up with noticeably less plaque buildup. It’s been a great way to support my gut and oral microbiome together.

6️⃣ Fixing the Damage – For my patients who already had damage from mouth breathing, the priority was remineralizing and protecting their teeth ASAP. That meant using nano-hydroxyapatite toothpaste and ensuring they were properly cleaning between their teeth—especially in dry areas where plaque buildup was worse. This electric flosser became a game-changer for removing hidden buildup.

This email is brought to you by BIOptimizers
I used BIOptimizers’ Magnesium Breakthrough for many years before they reached out to partner with me. It’s the only magnesium supplement I have found that contains all seven essential forms—which is critical for sleep, recovery, and saliva quality. I highly recommend it and take it myself every single day. I love receiving messages from all of you telling me how much this magnesium supplement has changed your lives.

Try it out for yourself. They have a 365-day return policy—that’s how confident they are in their product. Use my code for a discount:
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Wishing you a wonderful week,

Mark

P.S. Small changes add up. If you’ve been dealing with dry mouth or unexplained cavities, try these tweaks—you might be surprised at how big of a difference they make! 🚀