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

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:

A banana-based smoothie (high-PPO drink) with added flavan-3-ols
A mixed berry smoothie (low-PPO drink) with added flavan-3-ols
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

Skip the banana if polyphenols are your priority. Use mango, pineapple, orange, or frozen cauliflower for creaminess instead.
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.
Drink smoothies immediately after blending. Flavanols degrade rapidly once exposed to PPO — don’t let smoothies sit for more than a few minutes.
Add your cocoa and berries to low-PPO bases. Combine cocoa powder or berry blends with pineapple, mango, yogurt, oat milk, or almond milk.
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.

Red and Purple for a Happy Gut and Glowing Skin

Unlocking the Secrets of Polyphenols and Akkermansia

We’re learning that gut health is about so much more than digestion. The gut plays a vital role in immune regulation, metabolism, mood, and even skin health. One of the biggest reasons for this connection lies in the gut barrier, a protective mucosal “firewall” that keeps inflammation and unwanted immune activation in check.

When this barrier becomes compromised, it can trigger a cascade of inflammation that often shows up on the skin in the form of acne, rosacea, eczema, or premature aging.

One of the most fascinating ways to support both gut and skin health is through polyphenols, the colorful plant compounds found in foods like pomegranate, cranberry, and dragon fruit. These nutrients nourish beneficial gut microbes such as Akkermansia muciniphila, which play a key role in maintaining a strong, healthy gut lining.

Let’s dive into how these vibrant foods can support a balanced microbiome, a resilient gut barrier, and a glowing complexion.

What Are Polyphenols?

Polyphenols are naturally occurring compounds found in colorful fruits, vegetables, herbs, and drinks like tea and coffee. They protect plants from environmental stressors, and when we consume them, they do the same for our bodies.

In the gut, polyphenols act as prebiotic-like nutrients that feed beneficial microbes. When these microbes metabolize polyphenols, they produce smaller compounds that help lower inflammation, balance the immune system, and strengthen the gut lining.

A strong gut lining is essential for clear, resilient skin. When that inner barrier remains intact, it helps prevent inflammatory molecules from entering the bloodstream and affecting the skin’s outer barrier.

Top Food Sources of Polyphenols

Meet Akkermansia muciniphila: Your Gut’s Best Friend

Red and purple fruits such as pomegranate, cranberries, and dragon fruit
Berries (blueberries, raspberries, strawberries)
Dark chocolate and cocoa
Green and black tea
Coffee
Olive oil
Herbs and spices (turmeric, cinnamon, oregano, rosemary)

Akkermansia muciniphila is one of the most intriguing bacteria in the gut. It lives in the mucus layer that lines the intestines and helps maintain a healthy gut barrier—your body’s first line of defense against inflammation.

Here’s why Akkermansia matters for gut and skin health:

Gut Barrier Support: Akkermansia consumes mucin (a key component of mucus), stimulating the gut to produce more. This helps thicken the intestinal barrier and maintain integrity.
Short-Chain Fatty Acid Production: As it breaks down mucin, Akkermansia produces short-chain fatty acids (SCFAs) such as acetate. These compounds nourish other beneficial bacteria that produce butyrate, an essential energy source for colon cells.
Metabolic and Skin Benefits: Healthy levels of Akkermansia are linked to better blood sugar balance and reduced systemic inflammation, both of which influence skin clarity and texture.
Immune Regulation: By supporting a strong mucosal firewall, Akkermansia helps calm overactive immune responses that can manifest as skin irritation or redness.

Low Akkermansia levels have been associated with inflammatory bowel conditions, metabolic imbalance, and systemic inflammation that can show up on the skin. On functional stools tests, I often see very low akkermansia with my chronic skin condition clients, especially acne.

The Dynamic Duo: Polyphenols and Akkermansia

Research shows that certain polyphenols, especially those found in pomegranates, cranberries, and dragon fruit, help feed and promote Akkermansia muciniphila. This synergy supports gut barrier strength and helps keep inflammation under control—key for both gut and skin balance.

Pomegranate: The Ellagitannin Powerhouse

Pomegranates are rich in ellagitannins, which gut bacteria convert into beneficial compounds called urolithins. These metabolites have powerful anti-inflammatory effects and have been shown to encourage Akkermansia growth.

By strengthening the gut barrier and reducing systemic inflammation, pomegranate compounds may also help reduce skin redness and promote a smoother, more even complexion.

Ways to add pomegranate:

Sprinkle arils on yogurt, oatmeal, or salads
Enjoy a small glass of 100% pomegranate juice
Use pomegranate molasses as a glaze for vegetables or meats

Cranberries: The Proanthocyanidin All-Stars

Cranberries are best known for supporting urinary tract health, but they’re also rich in proanthocyanidins (PACs) that benefit the gut lining and microbiome. These PACs appear to feed Akkermansia and strengthen the mucosal layer.

Cranberries’ antioxidant and anti-inflammatory properties can help calm internal sources of inflammation that often contribute to skin flare-ups and dullness.

Easy ways to enjoy cranberries:

Add unsweetened dried cranberries to trail mix or granola
Make a fresh cranberry sauce with minimal added sugar
Blend unsweetened cranberry juice with sparkling water
Add cranberry powder to smoothies

Dragon Fruit: The Vibrant Polyphenol Booster

Dragon fruit, especially the red and magenta varieties, is rich in polyphenols, flavonoids, and betacyanins—powerful antioxidants that protect against oxidative stress and inflammation.

These compounds, including gallic acid, caffeic acid, and ferulic acid, support a healthy gut barrier while helping calm inflammation that can show up on the skin. By nurturing Akkermansia and other beneficial microbes, dragon fruit supports both gut balance and skin radiance.

How to add dragon fruit to your diet:

Blend into smoothie bowls
Add to yogurt or chia pudding
Enjoy fresh as a hydrating, gut-friendly snack

A Word on Supplements

You can find polyphenol supplements that include pomegranate and cranberry, and there are high-quality options out there.

Whenever possible, aim to get your polyphenols from whole foods first. Whole foods provide a complex matrix of fibers, antioxidants, and nutrients that work together to nourish your gut microbes, maintain your mucosal barrier, and support skin from within.

Evidence for the Benefits of Polyphenol-Rich Foods

A study in older adults residing in a care facility found that a polyphenol-rich diet improved intestinal barrier integrity, partly through modulation of the gut microbiome. Participants with elevated intestinal permeability consumed three daily servings of polyphenol-rich foods, including berries, pomegranate juice, green tea, and dark chocolate, for eight weeks. Following the intervention, zonulin levels (a key marker of intestinal permeability) significantly decreased. Higher polyphenol intake was also positively associated with the abundance of short-chain fatty acid–producing bacteria, which support colonic health and act as important signaling molecules. In contrast, pathogenic species showed a negative correlation with polyphenol consumption.

Servings from the study included:

3/4 cups of blueberries

1 cup of green tea

1/2 teaspoon cocoa powder

1 apple

1/2 cup pomegranate juice

If you want to boost your gut and support glowing skin, aim for 3 servings a day polyphenol-rich foods.

A colorful and varied diet provides a spectrum of plant compounds that work together to reduce inflammation, strengthen your gut’s mucosal firewall, and support a clear, healthy complexion.

The Takeaway

The gut and skin are deeply connected through the health of the gut’s mucosal barrier. When this barrier is strong, it acts like a firewall, keeping inflammation under control and supporting skin clarity, hydration, and resilience.

Polyphenol-rich foods—especially red and purple ones like pomegranates, cranberries, and dragon fruit—help beneficial bacteria such as Akkermansia muciniphila thrive. These compounds strengthen the gut barrier, reduce inflammation, and bring your skin’s natural glow to the surface.

So go ahead and paint your plate with the colors of health—your gut and skin will thank you.

Acknowledgments

Special thanks to Victoria R. Barreras for contributing.

References

Hu, Z., Xu, Y., Xiong, Y., & Huang, G. (2025). Mechanisms, Functions, Research Methods and Applications of Starch-Polyphenol Complexes in the Synergistic Regulation of Physiological Parameters. Foods (Basel, Switzerland), 14(18), 3219. https://doi.org/10.3390/foods14183219
Rasouli, H., Farzaei, M. H., & Khodarahmi, R. (2017). Polyphenols and their benefits: A review. International journal of food properties, 20(sup2), 1700-1741.
Abbas, M., Saeed, F., Anjum, F. M., Afzaal, M., Tufail, T., Bashir, M. S., … Suleria, H. A. R. (2016). Natural polyphenols: An overview. International Journal of Food Properties, 20(8), 1689–1699. https://doi.org/10.1080/10942912.2016.1220393
Peron G, Gargari G, Meroño T, Miñarro A, Lozano EV, Escuder PC, González-Domínguez R, Hidalgo-Liberona N, Del Bo’ C, Bernardi S, Kroon PA, Carrieri B, Cherubini A, Riso P, Guglielmetti S, Andrés-Lacueva C. Crosstalk among intestinal barrier, gut microbiota and serum metabolome after a polyphenol-rich diet in older subjects with “leaky gut”: The MaPLE trial. Clin Nutr. 2021 Oct;40(10):5288-5297. doi: 10.1016/j.clnu.2021.08.027. Epub 2021 Sep 9. PMID: 34534897.