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Eczema and Cavities in Children: The Hidden Connection Parents Miss

Eczema and Cavities 

If your child’s eczema won’t go away… read this.

You’ve cleaned up their diet.
You’ve removed the “usual suspects.”
You’ve tried everything you’ve been told should work.

And yet… the rashes keep coming back.

What if the real trigger isn’t food at all?

A Story You Might Recognize

One of my pediatric clients had been eczema-free for almost a full year.

Then suddenly—they flared again.

At first, it seemed obvious:
Springtime. Allergies. Environmental triggers.

But then her mom mentioned something unexpected…

👉 She had two large cavities in her baby teeth

Her dentist wasn’t overly concerned long-term, but the cavities were significant and recommended helping the teeth fall out sooner.

So they did.

And then something surprising happened:

✨ The teeth came out
✨ The eczema disappeared
✨ And they haven’t returned since

Coincidence? Maybe.

But it raises an important question:

👉 Could what’s happening in the mouth be affecting the skin?

The Overlooked Connection: Cavities & Skin Health

Most parents are told to focus on food triggers when it comes to eczema.

But research shows something interesting:

👉 Kids (and adults) with eczema are more likely to have dental cavities and oral health issues

This points to a deeper connection:

Both conditions are driven by inflammation and microbiome imbalances.

Why the Mouth Matters (More Than You Think)

Here’s something most people don’t realize:

👉 You swallow 1–2 liters of saliva every day

That means whatever is happening in the mouth—
 good or bad—is constantly being sent into the gut.

So if your child has:

  • Cavities
  • Bacterial overgrowth
  • Oral infections

That doesn’t stay in the mouth.

It becomes a daily source of inflammation affecting the entire body.

This Changes Everything

Because now, instead of asking:

❌ “What food is causing this?”

You can ask:

✅ “Where is inflammation coming from?”

Common Root Causes Behind Skin Flares

When I work with clients, we look beyond food and into the bigger picture:

✔️ Gut imbalances
✔️ Oral microbiome issues (like cavities)
✔️ Immune system dysregulation
✔️ Nutrient deficiencies

These are the real drivers of chronic skin issues.

Signs You Might Be Missing a Key Piece

You may want to explore oral health deeper if:

  • Your child’s skin isn’t improving despite dietary changes
  • You keep removing foods with little progress
  • Flare-ups feel random or cyclical
  • There’s a history of cavities or dental concerns

What to Do Next

Instead of continuing to restrict more foods, shift your focus:

👉 Look at the body as a whole
👉 Address hidden sources of inflammation
👉 Support the gut + immune system together

Because when you target the root cause…

✨ Skin starts to calm
✨ Diets expand (not shrink)
✨ And healing becomes sustainable

Final Takeaway

What happens in the mouth doesn’t stay in the mouth.

It can directly impact your child’s gut, immune system, and skin.

And sometimes, the missing piece in stubborn eczema… isn’t another food to remove.

It’s a source of inflammation you haven’t addressed yet.

If you want help identifying what’s actually driving your child’s skin:

👉 Book a discovery call:
https://dermadietitian.com/discovery-call/

No more guessing—just real answers.

Nighttime Itching in Kids: Why Eczema Flares After Dark

Why Is My Child’s Eczema Worse at Night?

If your child seems fine during the day but suddenly becomes very itchy at bedtime, you are not imagining it. Nighttime itching is one of the most common (and frustrating) symptoms of eczema in kids.

The good news is there are real, biological reasons behind it — and understanding them can help you better support your child.

The Body’s Internal Clock Plays a Role

Your child’s body follows a natural 24-hour rhythm called the circadian rhythm. This internal clock affects skin hydration, inflammation, hormone levels, and even how strongly itch is perceived.

At night, several of these factors shift in a way that makes eczema symptoms worse.

The Skin Gets Drier at Night

In the evening, the skin naturally loses more water. This process, called transepidermal water loss, leads to increased dryness.

For children with eczema, whose skin barrier is already compromised, this can significantly increase irritation and itching. On top of that, oil production drops at night, leaving the skin with less natural protection.

Inflammation Increases Overnight

The immune system becomes more pro-inflammatory at night. This means the signals that trigger itching become more active, while calming, anti-inflammatory signals decrease.

Cortisol, the body’s natural anti-inflammatory hormone, is also at its lowest level during the night, which can allow inflammation and itch to flare.

Skin Becomes More Sensitive

Blood flow to the skin increases in the evening, which can make the skin more reactive and sensitive. This can intensify the feeling of itching, even if the rash itself has not changed much.

Less Distraction Makes Itch Feel Worse

During the day, your child is distracted by activity and play. At night, everything becomes quiet, and the itch becomes much more noticeable.

Scratching often happens during lighter stages of sleep and can take up a significant portion of the night, leading to disrupted sleep and overtired kids.

Melatonin and Sleep Challenges

Melatonin, the hormone that helps regulate sleep, may be lower or disrupted in children with eczema. This can make it harder to fall asleep and may worsen overall symptoms.

Some research suggests that supporting healthy melatonin levels may improve both sleep and eczema severity.

Supporting Comfort While Addressing Root Causes

While simple routine changes can help ease discomfort and reduce nighttime itching, they are best used as supportive tools rather than a complete solution. Steps like applying a thick, fragrance-free moisturizer before bed, using lukewarm baths followed by immediate moisturizing, keeping the bedroom cool, and choosing soft, breathable fabrics like cotton can all help your child feel more comfortable.

However, if your child’s eczema or nighttime itching is ongoing, it is usually a sign that there are deeper underlying factors at play. True, long-term improvement comes from identifying and addressing those root causes. In my experience, this often includes immune system imbalances, low-grade chronic infections, and gaps in diet quality that contribute to ongoing inflammation and skin flare-ups.

If you want personalized support for your child, you can book a discovery call here to take the first step in your child’s healing journey.

References

https://onlinelibrary.wiley.com/doi/10.1111/pde.13364

https://pubmed.ncbi.nlm.nih.gov/38305093/

https://pubmed.ncbi.nlm.nih.gov/12606187

Is Food Really Causing Your Child’s Rashes?

Is Food Really Causing Your Child’s Rashes?

Why It’s Typically Not About the Food

If your child has mysterious rashes or hives, it’s natural to look straight at what they’re eating. Parents often say, “It must be dairy,” “Maybe it’s gluten,” or “Was it the strawberries?” It feels logical: food goes in, rash shows up, so the food must be the problem. Believe me, I have been there!

But for most kids with ongoing rashes and hives, food is not the true root cause. Food is more like a visitor walking through a neighborhood. If the neighborhood is calm and well-kept, that visitor can pass through without drama. If the neighborhood is already chaotic, one extra visitor might spark trouble—but the real issue is the state of the neighborhood, not the visitor itself.

In your child’s body, that “neighborhood” is the gut and immune system. When that environment is imbalanced and inflamed, everyday foods get blamed for symptoms that actually began long before the meal.

The Immune System’s Headquarters Lives in the Gut

We often think of the immune system as something floating around in the blood, but a huge portion of it actually lives in and around the gut. The lining of the intestines is surrounded by immune tissue and immune cells that are constantly sampling what comes through—food, microbes, and other particles—and deciding what is safe and what might be dangerous.

Scientists estimate that most immune cells reside in gut-associated lymphoid tissue, where they are in close contact with the trillions of microbes that live in the digestive tract. This means the gut is not just a “tube” for digestion; it is a training ground where the immune system learns what to tolerate and what to react to.

When this training environment is healthy, kids are generally more tolerant of a wide variety of foods and less prone to chronic inflammatory symptoms like eczema, rashes, and hives. A large study following over 1,000 kids found that when a baby’s gut bacteria weren’t developing well by age 1, they were more likely to have allergies by age 5.

Meet the “Neighborhood”: The Gut Microbiome

Think of your child’s gut like a bustling city full of “microbe neighbors.” There are friendly, hard-working microbes that help keep things running smoothly, neutral ones just passing through, and troublemakers that can stir up problems if they get too numerous.

In a healthy gut “city,” the friendly microbes are plentiful. They help digest food, produce beneficial compounds, and send calming signals to the immune system. They also help crowd out more harmful microbes. When this city is well-balanced, the immune system is less likely to overreact to normal daily exposures, including food.

When the balance shifts—if beneficial microbes are low and opportunistic or pathogenic microbes overgrow—the city becomes more chaotic. This imbalance, called dysbiosis, can alter how the immune system behaves and set the stage for inflammation that may show up on the skin.

The Gut Barrier: Your Child’s “Security Fence”

The gut lining acts like a highly selective fence or security gate. It’s designed to let in nutrients and beneficial compounds while keeping out larger, unwanted particles and microbes. Picture a gated community where the security team checks IDs before letting anyone in.

When the gut barrier is strong, only the right things pass through into the bloodstream. The immune system behind that fence sees mostly what it expects to see and stays relatively calm.

But if that fence becomes damaged or “leaky”—due to infections, chronic inflammation, dysbiosis, or other stressors—more unfiltered material gets through. Larger fragments of food, bacterial products, and toxins can slip past the gate and come into contact with immune cells that were never meant to see them.

At that point, the immune system can go on high alert. That heightened reactivity doesn’t stay confined to the gut; it can show up as inflammation in other parts of the body, including the skin. So when your child eats a perfectly normal food while their gut barrier is compromised, that food can appear to “trigger” a rash, even though the underlying problem is the leaky, inflamed fence—not the food itself.

The Gut–Immune–Skin Axis: How the Gut Talks to the Skin

Researchers now describe a “gut–skin axis”—a communication highway between the microbes and immune cells in the gut and the cells and immune activity in the skin.

When the microbiome is healthy, beneficial bacteria produce compounds (such as short-chain fatty acids) that help reinforce the gut barrier and support regulatory immune cells—the peacekeepers that prevent overreactions. This helps promote tolerance so the body is less likely to see everyday foods and environmental exposures as threats.

When the microbiome is imbalanced and the barrier is compromised, those calming signals drop, and more inflammatory signals circulate. Over time, that can contribute to conditions like eczema, rashes, and even chronic hives. In many children, changes in the gut environment can be present well before obvious skin symptoms appear.

When Food Really Is the Culprit

To be clear, there are times when specific foods truly are the problem. This is especially true in classic IgE-mediated food allergies. In this situation, the immune system has created specific IgE antibodies against a food protein—like peanuts, milk, or egg.

When the child eats that food, the immune system immediately recognizes it and releases histamine and other chemicals, triggering rapid symptoms such as hives, swelling, vomiting, or breathing difficulties. These reactions are usually obvious and reproducible: the same food causes a similar reaction every time, often within minutes to two hours.

These are serious reactions that require medical evaluation and guidance from an allergist. In these cases, strict avoidance of the culprit food is appropriate and essential for safety. But this is not what’s happening in the majority of kids with ongoing, non-specific rashes or chronic hives. In fact, a major JAMA review on chronic spontaneous hives found that true IgE food allergy was identified in only about 1.5% of patients. Leading international urticaria guidelines likewise state that food allergy is an extremely rare cause of chronic hives, and allergy society guidelines echo this conclusion.

Chronic Hives: Why Food Is Rarely the Main Driver

Many parents assume that daily or long-standing hives must be due to something in the diet. However, clinical guidelines emphasize that chronic hives (lasting more than six weeks) are rarely caused by food. Broad elimination diets often do little to change the pattern of hives in these kids.

Instead, chronic urticaria is frequently linked to internal immune dysregulation, infections, medications, physical triggers (like pressure or temperature changes), or is classified as chronic spontaneous urticaria when no clear external trigger is found.

This doesn’t mean food is irrelevant, but it does mean that food is often not the root cause. If the immune system is already on edge due to gut dysbiosis, infections, or other internal factors, a meal may appear to “set off” hives simply because the system was primed and ready to flare.

Why Food Gets Blamed: The Spark vs. the Kindling

Let’s use another metaphor: imagine a campfire. The kindling and logs are the fuel; the match is just the spark. If there’s no fuel, the match does nothing. If there’s a big pile of dry logs, one small spark can start a blaze.

In this context:

  • The “kindling and logs” are the child’s internal environment: gut microbiome balance, gut barrier integrity, and underlying immune regulation.

  • The “match” is the food or exposure present at the time symptoms appear.

If the internal environment is calm and well-regulated, an occasional spark (like a common food or exposure) doesn’t lead to ongoing fire. If the environment is already dry and loaded with fuel—because of dysbiosis, a leaky gut barrier, or ongoing inflammation—almost any spark can seem like the culprit.

This is why I hear parents say “every time my child eats X, their rash seems worse,” even though that same food might be tolerated in a healthier gut environment. The food is easier to see and control than the invisible gut–immune network, so it gets blamed—but it isn’t always the true problem.

When You Should Still Investigate Food

Even though food is often not the primary driver of chronic rashes or hives, there are clear situations when a focused food evaluation is important:

  • Reactions are immediate and repeatable with the same food (for example, hives, swelling, or vomiting within minutes to two hours of eating it).

  • Symptoms include breathing difficulty, throat tightness, severe swelling, or other signs of anaphylaxis (always an emergency).

  • Your child has a known history of allergies and develops new, consistent reactions tied to specific foods.

In these cases, working with an allergist to identify or rule out true food allergy is essential. This allows you to make targeted, medically guided changes rather than broad, stressful food elimination.

Shifting the Focus: From Restriction to Environment

Many families’ first instinct with skin symptoms is to cut more and more foods from their child’s diet. Over time, this can become exhausting, stressful, and even nutritionally limiting—especially for kids who are still growing. I see this all the time in my practice. Yet what these children truly need for skin repair is more nourishment, not less—especially plenty of protein and antioxidant-rich foods to give their skin the building blocks it needs to heal.

There’s also strong evidence that constantly removing and avoiding foods can actually backfire, increasing the risk of IgE‑mediated food allergies in kids. This seems to happen in two main ways: when children miss the critical early window to build oral tolerance to foods, and when unnecessary long‑term restriction causes them to lose tolerance they once had.

If an allergy workup has not identified clear food allergies, or if hives and rashes continue despite multiple diet changes, it may be more helpful to shift attention away from “What food should we remove next?” and toward “What is going on in my child’s gut and immune environment?”

In my practice, that might include:

  • Supporting a healthy, diverse overall diet rather than focusing only on restriction

  • Looking at gut health, microbial balance, and possible infections or overgrowths

  • Considering factors that impact the gut barrier

  • Addressing broader drivers of inflammation, not just what shows up on the plate

The goal is to create a calmer, more resilient internal environment so your child’s immune system is less reactive in general. Then, everyday foods are more likely to be tolerated instead of blamed.

A New Way to Talk About Your Child’s Rashes

When you talk to your child—or to yourself—about their skin symptoms, you might reframe the story like this:

  • “Your body isn’t broken; it’s just sending us messages that something inside needs support.”

  • “Instead of blaming the food, we’re going to look at the ‘neighborhood’ in your belly and help calm things down.”

  • “We want your gut and immune system to feel safe and steady so your skin can show that calm on the outside.”

This shift—from fear and restriction toward curiosity and root-cause support—can be deeply relieving for both caregivers and kids. Instead of waging war on your entire pantry, schedule a 30‑minute discovery call with me, The Derma Dietitian®, so we can map out the next steps in your child’s healing journey and address the gut–immune–skin connection that so often drives those stubborn rashes and hives.

References

https://pubmed.ncbi.nlm.nih.gov/23845860/

https://pubmed.ncbi.nlm.nih.gov/37747742/

https://pubmed.ncbi.nlm.nih.gov/42083785/

https://pubmed.ncbi.nlm.nih.gov/39078229

https://pubmed.ncbi.nlm.nih.gov/37644001

https://jamanetwork.com/journals/jama/article-abstract/2824115?utm_source=openevidence&utm_medium=referral

https://onlinelibrary.wiley.com/doi/10.1111/all.13397

postbiotic supplement for constipation

The Supplement I Never Expected to Love (But Can’t Stop Talking About)

Spotlight on ThaenaBiotic®

There are supplements I recommend because the research is solid. And then there are supplements I recommend because I’ve felt the difference myself — and then dug into the research. Thaena falls squarely in the second category.

If you’ve been following along, you know gut health is at the center of almost everything I do — from stubborn skin flares to mood swings, energy crashes, and yes, the less glamorous stuff, like what’s (or isn’t) happening in the bathroom. So when I started noticing real changes in my own bowel regularity after adding ThaenaBiotic® to my routine, I had to share it with you.

So… What Even Is ThaenaBiotic®?

ThaenaBiotic® is the world’s first human-derived postbiotic supplement — and before you scroll away, let me explain why that’s actually brilliant.

You’ve probably heard of probiotics (live bacteria) and prebiotics (the fiber that feeds them). Postbiotics are the third piece of that puzzle: the actual metabolites — the tiny molecules — that healthy gut bacteria produce. Think of it this way:

Prebiotics are the fertilizer. Probiotics are the seeds. Postbiotics are the ready-to-harvest nutrients your gut cells immediately recognize and use.

ThaenaBiotic® is made from carefully screened, extraordinarily healthy human donors. Their stool is collected, rigorously sterilized using high-heat autoclaving (which kills all bacteria, fungi, and viruses), then freeze-dried and encapsulated. What remains is a complex, bioactive treasure chest of over 14,000 distinct metabolites that your gut knows exactly how to use.

No live bacteria. No refrigeration required. No colonization concerns.

Why I Started Using It (Hint: Constipation)

Constipation is one of those symptoms that sounds minor but is actually a significant sign that your gut ecosystem is struggling. I tried Thaena because I wanted to see firsthand what all the buzz was about — and the results genuinely surprised me.

Here’s the science behind why it helps with motility and regularity:

ThaenaBiotic® is rich in short-chain fatty acids (SCFAs) like butyrate, which directly fuel colon cells, support gut barrier integrity, and help regulate the muscular contractions that move stool through your digestive tract. It also contains secondary bile acids (like lithocholic acid) that bind to receptors enhancing gut motility — and indoles, tryptophan-derived compounds that help modulate gut inflammation and support smooth digestive signaling.

In short: it restores the molecular signals your gut needs to remember how to move.

Real users echo this experience. One ThaenaBiotic® user shared: “I’m experiencing an improvement not only with bowel movements, but also with gut tolerance. I have started to carefully and slowly include raw vegetables in the form of salad and very slowly introducing raw apple. Both of which I am tolerating.”

The Bonus Benefits: Sleep & Mood

Here’s where it gets really interesting from a gut–brain axis perspective.

When your gut microbiome is depleted or out of balance, your body loses access to key signaling compounds that regulate far more than digestion — including energy metabolism, stress resilience, and mood. The gut–brain axis is a constant, two-way communication highway between your enteric nervous system (your “second brain” in your GI tract) and your central nervous system.

Several of the metabolites in ThaenaBiotic® are directly implicated in this crosstalk:

  • Indole-3-propionic acid (IPA) and related indoles can activate receptors that calm inflammation, protect nerve cells, and support balanced immune and emotional responses
  • Butyrate and propionate (SCFAs) have been shown in emerging research to interact with cells involved in mood regulation and stress responses
  • Urolithin A (a polyphenol-derived metabolite) supports mitochondrial function via mitophagy — essentially cellular “spring cleaning” — which can influence both energy and cognitive clarity
  • Inosine (a nucleotide derivative) gently modulates immune responses and supports tissue repair and energy metabolism

Many users report noticing changes in how “foggy” or energized they feel as gut balance improves — and individual responses will vary, but the biological rationale is sound.

Who This Is For

ThaenaBiotic® isn’t just for people with constipation. It may be a fit if:

  • You’ve tried probiotics and still don’t feel right. Most probiotics add a few lab-grown strains to a gut with trillions of microbes — their effects are often temporary. ThaenaBiotic® delivers what the gut actually uses: the postbiotic signals that tell your body how to regulate itself.
  • You’re recovering from antibiotics, illness, or burnout. When a course of antibiotics or a prolonged illness depletes your microbiome, you lose access to key compounds that regulate digestion, energy, and mood. ThaenaBiotic® replenishes those signals safely, without live bacteria.
  • Your diet is limited by food sensitivities. If you can’t tolerate certain foods, your microbes can’t make the nutrients those foods would normally create. Because Thaena’s donors eat a full spectrum of healthy foods, you get that full-spectrum postbiotic output even while your own diet is restricted.
  • You’re a high-optimizer looking for the missing piece. You track sleep, recovery, and every other metric — but your gut ecosystem may be the one system you haven’t fully optimized yet.

How to Take It

Simple dosing is part of ThaenaBiotic®: Take 1 capsule with or without food, morning or evening. No refrigeration needed.

The Risk-Free Part

They offer a 30-day money-back guarantee on a one-month supply — meaning you can test this for a full month and request a full refund if you don’t notice a difference. For a product this unique, that kind of confidence matters.

My Take 

As someone who works with clients on chronic skin and gut issues daily, I’m always looking for tools that address root-cause biology rather than just masking symptoms. The gut–skin–brain connection is real, and the postbiotic research emerging around metabolites like butyrate, indoles, and bile acid derivatives aligns with what I see clinically.

This isn’t a probiotic you take and forget. It’s a signal restoration tool — and it’s one I’m genuinely using and recommending right now.

Ready to Try It? 

You can order ThaenaBiotic®  through my practitioner portal. Please note that I earn affiliate commissions, which help support my work and research into the topicals and supplements I recommend.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Always consult your healthcare provider before starting a new supplement.

Berry smoothie for optimal polyphenol absorption

Polyphenol Absorption in Smoothies: Why Your Banana Is the Problem

Is Your Banana Blocking Your Polyphenols? What the Research Says About PPO and Flavanol Absorption

You’re doing everything right. You blend up a smoothie packed with blueberries, blackberries, and a scoop of cocoa powder — all beautifully rich in antioxidants and anti-inflammatory compounds. And then you toss in a banana for creaminess.

Here’s the problem: that banana may be quietly dismantling the nutritional power of everything else in your blender.

 

What Are Polyphenols — and Why Do They Matter for Your Skin?

Polyphenols are a broad class of bioactive plant compounds found in berries, cocoa, green tea, grapes, apples, and countless other whole foods. Within the polyphenol family, flavanols (also called flavan-3-ols) are among the most studied — and most relevant to skin and gut health.

Flavanols have well-documented anti-inflammatory properties. They scavenge free radicals, help modulate immune signaling, and support the integrity of the gut lining. Research also shows that polyphenols positively shift the composition of the gut microbiome — increasing beneficial strains like Lactobacilli, Bifidobacteria, and Akkermanisa Muciniphila, while inhibiting the growth of harmful bacteria.

This matters enormously for anyone with chronic skin conditions. Through the gut-skin axis — the bidirectional communication network between the gut and the skin — a disrupted gut microbiome can activate inflammatory signaling pathways that manifest directly in the skin, contributing to conditions like atopic dermatitis, acne, and psoriasis. Supporting the gut with polyphenol-rich foods is a dietary strategy for skin health.

But only if those polyphenols actually make it into your bloodstream.

The Banana Problem: Polyphenol Oxidase (PPO)

Bananas contain a naturally occurring enzyme called polyphenol oxidase (PPO). This is the same enzyme responsible for the browning that happens when you bruise or slice a banana — it oxidizes polyphenols in the fruit, converting them into compounds called quinones, which eventually form that characteristic brown melanin pigment.

When a banana is blended into a smoothie alongside polyphenol-rich foods like berries or cocoa, the PPO enzyme doesn’t just act on the banana’s own compounds — it goes to work on the flavanols from every other ingredient in the blender.

What the Research Reveals

A study published in the journal Food and Function by researchers at UC Davis (funded by Mars Edge) directly tested this effect. Here’s what they found:

Study Design:
Participants consumed one of three conditions:

  1. A banana-based smoothie (high-PPO drink) with added flavan-3-ols
  2. A mixed berry smoothie (low-PPO drink) with added flavan-3-ols
  3. A flavan-3-ol capsule alone (control)

Blood and urine samples were collected to measure how much of the flavanols were actually absorbed.

Key Findings:

  • The peak plasma concentration of flavan-3-ol metabolites after the capsule was 680 ± 78 nmol/L
  • The berry smoothie produced similar absorption levels to the capsule
  • The banana smoothie resulted in a peak concentration of only 96 ± 47 nmol/L — an 84% reduction compared to the capsule

That is a staggering difference. Essentially, blending a banana into a polyphenol-rich smoothie can reduce the usable flavanols you absorb by more than four-fifths.

What About Drinking Them Separately?

Researchers wondered if the issue was the physical mixing — perhaps the PPO was acting on flavanols before you even took a sip. To test this, they had participants drink the banana and the flavan-3-ols separately but simultaneously, preventing pre-ingestion contact.

The result? Plasma flavanol levels were still significantly reduced compared to no banana at all. This strongly suggests that the banana’s PPO remains active in the stomach and continues to degrade flavanols even during digestion.

In lab simulations, banana smoothie retained 68% of its PPO activity after being incubated under gastric conditions (pH 3, pepsin, 37°C for 2 hours). In other words, stomach acid doesn’t neutralize this enzyme — it keeps working inside you.

The Cocoa Connection

A separate line of research (referenced by Dr. Michael Greger of NutritionFacts.org) found that banana-based chocolate smoothies saw a 90%+ drop in cocoa flavanols within an hour of blending — with a half-life of approximately 10 minutes, meaning flavanol levels halved every 10 minutes the smoothie sat. When PPO inhibitors were added to block the enzyme, the effect disappeared entirely — confirming PPO was the culprit.

Why This Is Especially Relevant for Skin Health Clients

Polyphenols are not just nice-to-have antioxidants. For clients working to calm skin inflammation and restore microbial diversity in the gut, they are part of the therapeutic dietary foundation.

Research has shown polyphenol consumption is associated with:

  • Reduced inflammatory cytokines linked to acne and atopic dermatitis
  • Increased gut microbial diversity, particularly anti-inflammatory strains
  • Protection against oxidative stress that damages the skin barrier
  • Modulation of NF-κB and COX-2 inflammatory pathways relevant to eczema

Unknowingly blocking 84% of these compounds with a single smoothie ingredient is a meaningful clinical miss — especially if you are drinking smoothies daily as part of a skin-healing protocol.

High-PPO vs. Low-PPO Foods: A Quick Reference

Not all fruits are created equal when it comes to PPO activity. Here’s a breakdown:

PPO Level Examples Recommendation
High PPO Banana, avocado Limit or separate from polyphenol-rich foods
Low PPO Mixed berries, pineapple, orange, mango, yogurt Safe to blend with flavanol-rich ingredients
Rich in Flavanols Blueberries, blackberries, cocoa, apples, grapes Combine with low-PPO ingredients for maximum benefit

Practical Tips: How to Maximize Polyphenol Absorption

  1. Skip the banana if polyphenols are your priority. Use mango, pineapple, orange, or frozen cauliflower for creaminess instead.
  2. If you do use banana, keep it separate. Eat the banana on the side rather than blending it in — this limits contact time with other polyphenols, though some gastric degradation may still occur.
  3. Drink smoothies immediately after blending. Flavanols degrade rapidly once exposed to PPO — don’t let smoothies sit for more than a few minutes.
  4. Add your cocoa and berries to low-PPO bases. Combine cocoa powder or berry blends with pineapple, mango, yogurt, oat milk, or almond milk.
  5. Consider whole food polyphenol sources as part of a broader dietary pattern — green tea, dark chocolate, olive oil, and red berries are all high-flavanol options that don’t require blending.

The Bottom Line

Bananas are not a bad food. They provide potassium, fiber, and resistant starch — all valuable for gut health. But if your goal is to maximize the anti-inflammatory and skin-protective benefits of polyphenols — whether from berries, cocoa, or other flavanol-rich sources — blending them with banana can cut that benefit by up to 84%.

As always in nutrition: it’s not just what you eat, but how you eat it that determines what your body actually gets.

If you want to talk about building a dietary strategy that supports your skin health from the inside out, book a discovery call to learn more about working together.

References:

Ottaviani JI et al. (2023). Impact of polyphenol oxidase on the bioavailability of flavan-3-ols in fruit smoothies: a controlled, single blinded, cross-over study. Food and Function. DOI: 10.1039/d3fo01599h

Woo YR et al. (2024). Gut-skin axis review. Journal of Dermatological Science.

PMC (2024). The Promising Role of Polyphenols in Skin Disorders. PMC/NIH.

PMC (2025). Flavonoids as Natural Anti-Inflammatory Agents in Atopic Dermatitis. PMC/NIH.

NutritionFacts.org (2024). The Downside to Banana Smoothies for Polyphenol Absorption.

Resistant Starch for Gut and Skin Health

Unlock Gut & Skin Health: Why F. prausnitzii is Your New Best Friend (and How to Feed It!)

We’re diving deep into the fascinating world of your gut microbiome again, and this time, we’re shining the spotlight on a true superstar: Faecalibacterium prausnitzii (F. prausnitzii). This little microbe might have a name that’s hard to pronounce, but it plays a HUGE role in keeping your gut happy and your skin glowing. Think of it as the ultimate gut gardener, cultivating a healthy and balanced inner ecosystem.

Why is F. prausnitzii So Important for Gut Health?

F. prausnitzii is one of the most abundant and important bacteria in a healthy human gut. It’s a master at producing butyrate, a short-chain fatty acid (SCFA) that’s like a magic elixir for your gut lining. Here’s why butyrate, and therefore F. prausnitzii, is so crucial:
  • Fuel for Your Gut Cells: Butyrate is the primary energy source for the cells lining your colon (colonocytes), keeping them healthy and functioning optimally.
  • Anti-inflammatory Champion: Butyrate has potent anti-inflammatory properties. It helps to calm inflammation in the gut by inhibiting pro-inflammatory pathways (like NF-kB) and promoting the production of anti-inflammatory molecules (like IL-10).
  • Gut Barrier Protector: F. prausnitzii and butyrate help maintain a strong gut barrier, preventing “leaky gut” syndrome, where unwanted substances can leak from the gut into the bloodstream, triggering inflammation and contributing to various health problems.

Low F. prausnitzii: A Recipe for Gut (and Skin) Trouble

When F. prausnitzii levels are low, your gut can become vulnerable. Research has linked low abundance of this beneficial bacterium to several conditions, including:
  • Inflammatory Bowel Disease (IBD): Studies consistently show reduced F. prausnitzii in Crohn’s disease and ulcerative colitis patients.
  • Irritable Bowel Syndrome (IBS): Alterations in F. prausnitzii levels have also been observed in IBS.
  • Other Conditions: The list goes on, including liver diseases, metabolic disorders, and even neurological conditions.
 

The Gut-Skin Connection: What Does F. prausnitzii Have to Do with It?

Remember the “gut-skin axis”? It’s the communication highway between your gut and your skin. When your gut is inflamed and your gut barrier is compromised (partly due to low F. prausnitzii and butyrate), it can trigger systemic inflammation that manifests in your skin.
  • Inflammation: Reduced butyrate production can lead to increased inflammation, which is a key factor in many skin conditions, including acne, eczema, and psoriasis.
  • Skin Barrier: Butyrate may also play a role in maintaining a healthy skin barrier, protecting against irritants and dryness.
  • Immune Modulation: The gut microbiome influences the immune system, and imbalances can contribute to skin conditions with an immune component.
  • Atopic Dermatitis (eczema): Research suggests a link between lower levels of F. prausnitzii and an increased risk of developing atopic dermatitis in infants.
 

How to Feed Your F. prausnitzii and Boost Gut & Skin Health

The good news is that you can nourish your F. prausnitzii population through your diet! The key is resistant starch, a type of carbohydrate that resists digestion in the small intestine and travels to the colon, where it serves as a feast for F. prausnitzii and other beneficial bacteria. Top Sources of Resistant Starch:
  • Cooked and Cooled Potatoes: The process of cooking and then cooling potatoes (especially overnight in the fridge) significantly increases their resistant starch content. Think potato salad, or simply enjoy cold, cooked potatoes as a side dish. You can also dice cooked and cooled sweet potatoes and freeze. Add ¼ cup to smoothies for a creamy consistency.  
  • Cooked and Cooled Rice: Similar to potatoes, when you cook and cool rice, some of the starch retrogrades into resistant starch. Leftover rice mixed into a green salad or sushi are great options.
  • Green Bananas: Unripe, green bananas are excellent sources of resistant starch. They’re less sweet than ripe bananas and can be added to smoothies for a creamy texture.
  • Oats: Choose uncooked rolled oats or make overnight oats by soaking them in liquid (like a dairy-free milk) in the fridge.
  • Legumes: Beans, lentils, and peas contain resistant starch, especially when cooked and cooled. Try a bean dip as your snack.
This information is for informational purposes only and is not intended as medical advice. Always consult with a healthcare professional before making significant changes that may impact your health.

The Bottom Line

F. prausnitzii is a crucial player in gut health, and a healthy gut is essential for healthy skin. By incorporating resistant starch into your diet, you can feed this beneficial bacterium, boost butyrate production, reduce inflammation, and support both your gut and your skin from the inside out. In The Derma-Gut Conncetion™ program we test for this marker as well as many more to see what’s going on inside your gut and how it’s impacting your skin. Imagine having a clear, personalized roadmap to achieving the healthy, radiant skin and vibrant gut health you deserve. Schedule a discovery call to learn more. 

Acknowledgments

Special thanks to Victoria R. Barreras for contributing.

References

Parsaei, M., Sarafraz, N., Moaddab, S. Y., & Ebrahimzadeh Leylabadlo, H. (2021). The importance of Faecalibacterium prausnitzii in human health and diseases. New microbes and new infections, 43. Song, H., Yoo, Y., Hwang, J., Na, Y. C., & Kim, H. S. (2016). Faecalibacterium prausnitzii subspecies-level dysbiosis in the human gut microbiome underlying atopic dermatitis. Journal of Allergy and Clinical Immunology, 137(3), 852-860.   This information is for informational purposes only and is not intended as medical advice. Always consult with a healthcare professional before making significant changes that may impact your health.  
Photo by Monika Grabkowska on Unsplash
Photo by Joshua Olsen on Unsplash
Photo by Melissa Di Rocco on Unsplash
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