Leaky Gut: The Controversial Condition Linked to Everything (What Science Actually Shows + Leaky gut syndrome Healing Protocol)

Chronic bloating that won't quit. Unexplained food sensitivities that appeared out of nowhere. Brain fog. Fatigue. Skin issues. Joint pain. Autoimmune disease.

If you've been dealing with vague, multi-system symptoms that doctors can't explain, you may have encountered the controversial diagnosis of "leaky gut syndrome" — or as it's known in medical literature, increased intestinal permeability.

Here's where it gets interesting:

Functional medicine doctors say leaky gut is the root cause of countless chronic conditions — from autoimmune diseases to depression.

Many conventional gastroenterologists say "leaky gut syndrome" is pseudoscience, not a real diagnosis, and the wellness industry is exploiting desperate patients.

The actual science? Intestinal permeability is REAL, measurable, and linked to numerous conditions. But it's more nuanced than either side admits.

Recent research is game-changing: A 2021 clinical trial (the MaPLE study) showed that a polyphenol-rich diet — the exact compounds concentrated in cold-pressed juice — reduced zonulin levels (the biomarker for leaky gut) and improved intestinal barrier function in just weeks.

Let's separate fact from fiction and give you a science-backed healing protocol.

What is "Leaky Gut Syndrome"? (Intestinal Permeability Explained)

The Gut Barrier: Your Internal Fortress

Your intestinal lining is only one cell thick — the thinnest barrier between the outside world (food, bacteria, toxins) and your bloodstream.

This single-cell layer performs an impossible balancing act:

• Absorb nutrients from food into your bloodstream

• Block pathogens, toxins, and undigested food particles from entering

It does this through tight junctions — protein structures that act like gates between intestinal cells, controlling what passes through.

When healthy: Tight junctions stay closed, allowing only properly digested nutrients through.

When damaged: Tight junctions loosen, creating gaps. Larger molecules (undigested food particles, bacteria, toxins) slip through into the bloodstream.

This is increased intestinal permeability — or colloquially, "leaky gut."

Zonulin: The Gatekeeper Protein

In 2000, Dr. Alessio Fasano discovered zonulin — a protein that regulates tight junction opening.

How zonulin works:

• When triggered, zonulin signals tight junctions to open (normal, temporary)

• This allows controlled passage of nutrients and fluid

• Then tight junctions close again

• 
  

The problem: Certain triggers cause excessive zonulin release, keeping tight junctions open too long.

What triggers excess zonulin:

• Gluten (gliadin protein) — even in people without celiac disease

• Bacterial imbalances (dysbiosis)

• Chronic stress

• NSAIDs (ibuprofen, aspirin)

• Alcohol

• Poor diet (high sugar, processed foods)

The result: Chronic intestinal permeability. Your gut barrier stays compromised.

What Happens When Your Gut Leaks?

When undigested food particles, bacterial fragments (lipopolysaccharides/LPS), and toxins enter your bloodstream:

1. Immune system activates — Your body sees these as foreign invaders

2. Systemic inflammation — Immune response triggers throughout the body

3. Antibody production — Your immune system creates antibodies against these particles

4. Chronic immune activation — Over time, this can lead to autoimmune reactions

This explains why leaky gut is linked to so many conditions.

The Medical Controversy: Why Doctors Disagree

Side 1: Functional Medicine's Position

Their claim: Leaky gut is the ROOT CAUSE of most chronic disease — autoimmune conditions, allergies, depression, skin issues, obesity, and more.

Their evidence:

• Zonulin levels are elevated in autoimmune diseases, celiac disease, type 1 diabetes, and multiple sclerosis

• Clinical observation: patients improve when gut barrier is healed

• Research linking intestinal permeability to numerous conditions

Their treatment: Remove inflammatory foods (gluten, dairy, sugar), heal gut with supplements (L-glutamine, zinc, probiotics), reduce inflammation.

Side 2: Conventional Medicine's Skepticism

Their concern:"Leaky gut syndrome" is not an official diagnosis. The term is overused by alternative medicine to sell unnecessary tests and supplements.

Their evidence:

• Intestinal permeability exists, but doesn't cause the wide array of symptoms attributed to it

• Testing for leaky gut is not standardized

• Causation vs. correlation: does leaky gut CAUSE disease, or is it a RESULT of disease?

Their position: Treat diagnosed conditions (IBD, celiac, etc.) with evidence-based medicine. Don't blame vague symptoms on "leaky gut."

The Actual Science: What Research Shows

Here's what peer-reviewed research actually demonstrates:

PROVEN:

1. Intestinal permeability is real and measurable

   • Zonulin, lactulose/mannitol tests, and other biomarkers can measure gut barrier function

2. Increased permeability is associated with numerous conditions:

   • Autoimmune diseases: Celiac disease, type 1 diabetes, rheumatoid arthritis, Hashimoto's, lupus, multiple sclerosis

   • Inflammatory bowel disease: Crohn's disease, ulcerative colitis

   • Metabolic conditions: Obesity, insulin resistance, fatty liver disease

   • Neurological: Depression, anxiety, autism spectrum (gut-brain axis)

   • Skin conditions: Eczema, psoriasis, acne

3. Zonulin is elevated in these conditions

   • Dr. Fasano's research (published in top journals) confirms this

4. Certain triggers increase intestinal permeability:

   • Gluten (gliadin triggers zonulin in everyone, not just celiacs)

   • Dysbiosis (bacterial imbalance)

   • Chronic stress (via gut-brain axis)

   • NSAIDs, alcohol, extreme exercise

5. Polyphenols improve gut barrier function

   • The MaPLE Trial (2021): Polyphenol-rich diet reduced zonulin levels and improved intestinal permeability in older adults

   • This is HUGE for cold-pressed juice (concentrated polyphenols)

   • 
     

CONTROVERSIAL (Ongoing Debate):

1. Causation vs. correlation

   • Does leaky gut CAUSE these diseases, or is it a consequence of inflammation?

   • Likely bidirectional: gut barrier damage → inflammation → more barrier damage (vicious cycle)

2. "Leaky gut syndrome" as a diagnosis

   • No official diagnostic criteria

   • Symptoms are non-specific

   • Conventional medicine prefers to diagnose specific conditions (celiac, IBD, etc.)

3. Commercial testing validity

   • Zonulin tests exist but aren't standardized

   • Lactulose/mannitol tests are research tools, not routine clinical tests

   • 
     

The Symptoms: What People Experience

Intestinal permeability can manifest as:

Digestive Symptoms

• Chronic bloating and gas

• Diarrhea or constipation (or alternating)

• Food sensitivities (especially new ones)

• Abdominal pain or cramping

• IBS-like symptoms

  
  

Systemic Symptoms

• Fatigue — Chronic, unexplained exhaustion

• Brain fog — Difficulty concentrating, memory issues

• Skin issues — Eczema, acne, rashes, psoriasis

• Joint pain — Inflammation in joints

• Headaches or migraines

• Mood issues — Anxiety, depression (gut-brain axis)

• Seasonal allergies or new food allergies

• Autoimmune flare-ups

The pattern: Multiple systems affected. Symptoms don't fit into one neat category. Conventional tests come back "normal" but you still feel terrible.

What Damages Your Gut Barrier?

Understanding what harms intestinal integrity helps you avoid these triggers:

1. Gluten (Gliadin Protein)

The science: Gliadin (a component of gluten) triggers zonulin release in EVERYONE — not just people with celiac disease.

Research by Dr. Fasano shows that while celiacs have prolonged zonulin elevation, even healthy people experience temporary increased permeability from gluten.

For sensitive individuals: This temporary permeability becomes chronic with repeated exposure.

2. Dysbiosis (Bacterial Imbalance)

A healthy gut has diverse beneficial bacteria. Dysbiosis — overgrowth of harmful bacteria or loss of beneficial species — damages the gut barrier.

Causes of dysbiosis:

• Antibiotics (kill good bacteria)

• Low-fiber diet (beneficial bacteria need fiber)

• High sugar/processed food diet (feeds harmful bacteria)

• Chronic stress

• Medications (PPIs, NSAIDs)

  
  

3. Chronic Stress

The gut-brain axis is bidirectional. Stress hormones directly impact gut barrier function.

How stress damages the gut:

• Reduces blood flow to intestines

• Alters gut motility

• Changes microbiome composition

• Weakens tight junctions

• Increases inflammation

4. NSAIDs (Ibuprofen, Aspirin, Naproxen)

Over-the-counter pain relievers directly damage intestinal lining.

Mechanism: NSAIDs inhibit prostaglandin production, which is needed for gut barrier maintenance.

Result: Increased permeability, especially with chronic use.

5. Alcohol

Alcohol is directly toxic to intestinal cells and disrupts the microbiome.

Even moderate consumption increases intestinal permeability.

6. Ultra-Processed Foods

Emulsifiers (in processed foods) weaken the protective mucus layer.

Preservatives (sodium benzoate, potassium sorbate) harm beneficial gut bacteria.

High sugar feeds harmful bacteria and increases inflammation.

7. Extreme Exercise

Moderate exercise is beneficial, but prolonged high-intensity exercise (marathons, ultra-endurance events) diverts blood from the gut to muscles.

Result: Oxygen deprivation damages intestinal barrier.

This is why endurance athletes often have GI issues during events.

The Gut-Everything Axes: Why Leaky Gut Affects Your Whole Body

Recent research reveals that gut health influences systems throughout the body:

Gut-Brain Axis

• 90% of serotonin is produced in the gut

• Gut bacteria produce neurotransmitters (GABA, dopamine)

• Leaky gut → inflammation → crosses blood-brain barrier → neuroinflammation

• Linked to depression, anxiety, brain fog, even Alzheimer's

Gut-Skin Axis

• Gut inflammation manifests as skin inflammation

• Linked to eczema, psoriasis, acne, rosacea

• Healing gut often clears skin

Gut-Immune Axis

• 70-80% of immune system is in the gut (GALT - gut-associated lymphoid tissue)

• Leaky gut → chronic immune activation → autoimmune risk

Gut-Muscle Axis

• Emerging research shows gut microbiome affects muscle mass and performance

• Relevant for aging, sarcopenia, athletic recovery

  
  

The Game-Changing Research: Polyphenols Heal Leaky Gut

The MaPLE Trial (2021) is a landmark study on gut barrier healing:

Study design:

• Older adults with elevated zonulin (leaky gut)

• Randomized to polyphenol-rich diet vs. control

• 8 weeks

Results:

• Zonulin levels decreased (gut barrier improved)

• Inflammation markers decreased (reduced calprotectin)

• Gut microbiome improved (beneficial bacteria increased)

Key finding:A diet rich in polyphenols — the exact compounds concentrated in cold-pressed juice — healed the intestinal barrier.

Polyphenol sources in the study:

• Berries

• Dark leafy greens

• Apples

• Citrus

• Green tea

• Dark chocolate

  
  

Translation for Rejuv Juice: One 20oz cold-pressed juice delivers MORE polyphenols than most people consume in a day.

The Leaky Gut Healing Protocol (90 Days)

This protocol combines the latest research on gut barrier healing:

Phase 1: Days 1-30 (Remove & Reset)

Goal: Eliminate triggers, reduce inflammation, begin healing.

Remove These (Temporarily):

• Gluten (all sources)

• Dairy (especially if lactose intolerant)

• Alcohol (completely)

• NSAIDs (switch to alternatives with doctor's guidance)

• Ultra-processed foods

• Refined sugar

• Artificial sweeteners

  
  

Add These:

Supplements:

• L-glutamine: 5g 2x daily (primary fuel for intestinal cells)

• Zinc carnosine: 75mg 2x daily (heals gut lining)

• Probiotics: 50+ billion CFU, multi-strain

• Omega-3: 2-4g EPA/DHA daily (anti-inflammatory)

• Vitamin D: 2,000-5,000 IU daily (immune regulation)

Nutrition:

• Daily polyphenol-rich juice: 20oz (following MaPLE protocol)

• Bone broth: Daily (provides collagen for gut lining)

• Fermented foods: Sauerkraut, kimchi, kefir (build microbiome)

• Fiber diversity: 30+ different plant foods weekly (feeds beneficial bacteria)

Expected: Initial detox symptoms (fatigue, headaches, cravings) first 5-7 days as gut begins healing.

Phase 2: Days 31-60 (Heal & Restore)

Goal: Deep gut barrier repair, microbiome restoration.

Continue Phase 1, plus:

Add Supplements:

• Colostrum: 2-4g daily (contains growth factors for intestinal lining)

• Deglycyrrhizinated licorice (DGL): 500mg before meals (soothes gut lining)

• Quercetin: 500mg 2x daily (reduces zonulin, anti-inflammatory)

• Berberine: 500mg 2x daily (rebalances microbiome)

Nutrition:

• Increase daily juice to 2x daily (morning + afternoon)

• Add prebiotic foods (asparagus, garlic, onions, Jerusalem artichoke)

• Increase polyphenol diversity (berries, green tea, dark chocolate)

Lifestyle:

• Stress management (breathwork, meditation, therapy)

• 7-9 hours sleep (gut repairs during sleep)

• Moderate exercise (not extreme)

Expected: Digestive symptoms improving significantly, energy increasing, skin clearing, brain fog lifting.

Phase 3: Days 61-90 (Strengthen & Maintain)

Goal: Solidify gut barrier integrity, establish long-term habits.

Continue Phase 1 & 2, plus:

Strategic Reintroductions:

• Test one removed food every 4-5 days

• Track symptoms for 72 hours

• If no reaction, can add back occasionally

• If reaction, avoid for another 3-6 months

Optimize:

• Reduce supplements to maintenance doses

• Increase food-based probiotics and prebiotics

• Continue daily polyphenol juice (non-negotiable)

Long-term:

• 80/20 rule: 80% gut-healing foods, 20% flexibility

• Manage stress consistently

• Avoid NSAIDs when possible

• Limit alcohol to special occasions

Expected: Gut barrier significantly stronger, symptoms resolved or minimal, energy restored, autoimmune markers improving (if applicable).

Cold-Pressed Juice: The Polyphenol Powerhouse

Based on the MaPLE study, here's why cold-pressed juice is perfect for leaky gut healing:

What Polyphenols Do for Your Gut:

1. Reduce zonulin — Directly improves tight junction function

2. Decrease inflammation — Lower inflammatory markers throughout body

3. Support beneficial bacteria — Polyphenols are prebiotic

4. Provide antioxidants — Protect intestinal cells from oxidative damage

5. Improve mucus layer — Strengthen protective barrier

Our Gut Healing Juice Formulas:

MORNING GUT RESTORE JUICE (20oz)

Kale, spinach, green apple, cucumber, celery, lemon, ginger

Why: Maximum polyphenols from greens + fiber for microbiome

AFTERNOON INFLAMMATION FIGHTER (16oz)

Beet, carrot, blueberries, turmeric, ginger, lemon

Why: Polyphenols + anti-inflammatory compounds + prebiotic fiber

EVENING DIGESTIVE SOOTHER (12oz)

Cucumber, celery, fennel, mint, aloe vera, lemon

Why: Calming, soothing, digestive support

Testing: Should You Test for Leaky Gut?

Available Tests:

1. Zonulin (serum or stool)

   • Measures gut barrier function

   • Elevated = increased permeability

   • Available through: Vibrant Wellness, Diagnostic Solutions, Doctor's Data

2. Lactulose/Mannitol Test

   • Gold standard research test

   • Measures what passes through gut barrier

   • Less commonly available clinically

3. Comprehensive Stool Analysis

   • Assesses microbiome, inflammation, digestive function

   • Companies: GI-MAP, GI Effects, Gut Zoomer

4. Food Sensitivity Testing (IgG)

   • Controversial but can identify reactions

   • Helps guide elimination diet

     
     

Do You Need Testing?

Test if:

• You have diagnosed autoimmune disease

• Symptoms are severe and you need confirmation

• You want to track progress objectively

Don't test if:

• Budget is limited (use funds for healing foods/supplements instead)

• Symptoms clearly improve with protocol (response is the test)

Many people heal without testing by following the protocol and tracking symptom improvement.

When to See a Doctor

Seek medical care if:

• Blood in stool (could indicate IBD, ulcers, cancer)

• Severe abdominal pain

• Unintended weight loss (>10 lbs)

• Persistent diarrhea (>2 weeks)

• Fever with digestive symptoms

• Symptoms worsen despite protocol

Important: Leaky gut can coexist with serious conditions (celiac, IBD, SIBO). Get properly diagnosed.

The Bottom Line: Gut Barrier Health is Foundation

Whether you call it "leaky gut syndrome" or "increased intestinal permeability," the science is clear:

✅ Intestinal permeability is real✅ Zonulin regulates tight junctions✅ Multiple triggers damage gut barrier✅ Associated with numerous chronic conditions✅ Polyphenols heal the gut barrier (MaPLE study)✅ Comprehensive protocol can restore integrity

Cold-pressed juice provides:

• Concentrated polyphenols (proven to reduce zonulin)

• Anti-inflammatory compounds

• Prebiotic fiber for microbiome

• Nutrients that support gut healing

• Hydration for optimal digestion

  
  

This isn't pseudoscience — it's cutting-edge research applied to real healing.

Ready to Heal Your Gut Barrier?

Visit REJUVJUICE.com to:

• Order our Gut Healing Juice Collection (Morning Restore, Inflammation Fighter, Digestive Soother)

• Download our free 90-Day Leaky Gut Healing Protocol

• Learn about our Gut Reset Program (juice + supplements + guidance)

• Shop recommended gut healing supplements

Your gut barrier is one cell thick. Support it with the polyphenols it needs to heal.

EXPANDED LEAKY GUT CONTENT: Testing Controversy & SIBO Connection

The Zonulin Testing Controversy: What You Need to Know (2026 Update)

If you're researching leaky gut, you've probably seen zonulin testing marketed everywhere. Here's the truth about these tests — and why the science is more complicated than the marketing suggests.

The Promise of Zonulin Testing

Zonulin is the protein that regulates tight junctions. Testing for zonulin (in blood or stool) theoretically shows if your gut barrier is compromised.

Available zonulin tests:

• Serum zonulin (blood test)

• Stool zonulin (fecal sample)

• Zonulin antibodies (IgG, IgA, IgM)

The appeal: A simple test that tells you if you have leaky gut. Clear answer, clear treatment path.

The Problem: Zonulin Tests May Not Be Accurate

Recent research (2019-2024) revealed major issues:

1. Commercial ELISA kits are non-specific

   • A 2019 study in Gut journal showed that commercial zonulin tests don't actually measure zonulin accurately

   • They measure other proteins (including haptoglobin precursors) and give false readings

   • Most published studies using these tests have questionable results

2. Zonulin levels fluctuate dramatically

   • Levels change throughout the day (intraday fluctuations)

   • One reading may not be reliable

   • Repeat testing often gives different results

3. Poor correlation with actual permeability

   • Zonulin test results don't always match lactulose/mannitol tests (gold standard)

   • You can have high zonulin but normal gut barrier function

   • You can have low zonulin but still have intestinal permeability

4. Not clinically validated

   • FDA does not approve these tests

   • No standardization between labs

   • Conventional gastroenterologists don't use them

What Chris Kresser (Functional Medicine Leader) Says:

Dr. Kresser, a respected voice in functional medicine, published an article questioning zonulin testing:

His conclusion: "Given the issues with zonulin testing, I think it's clear that it's not the way to diagnose leaky gut. The antigenic permeability screen (testing antibodies against tight junction proteins and LPS) may be more useful."

His bigger point: "It's worth asking whether we should even bother testing for intestinal permeability. Leaky gut is almost always caused by something further upstream (food intolerances, SIBO, stress, infections). We need to address those factors regardless of whether someone has a leaky gut."

Better Testing Approaches (2026)

If you still want objective data, consider these alternatives:

1. Comprehensive Stool Analysis

Tests like GI-MAP, GI Effects, or Gut Zoomer assess:

• Microbiome composition (dysbiosis)

• Inflammation markers (calprotectin)

• Digestive function

• Pathogens, parasites, fungi

• Sometimes zonulin (as one of many markers)

Value: Identifies ROOT CAUSES (infections, dysbiosis) rather than just measuring permeability.

2. Antigenic Permeability Screen (Cyrex Array 2)

Measures antibodies against:

• Zonulin (IgG, IgA, IgM)

• Occludin (another tight junction protein)

• Actomyosin (structural protein)

• LPS (bacterial endotoxin that leaks through)

Theory: If your immune system is making antibodies against these gut barrier proteins, it suggests chronic permeability and immune activation.

More useful than zonulin alone — shows immune response pattern.

3. SIBO Breath Test (trio-smart)

Tests for:

• Hydrogen (bacterial fermentation)

• Methane (archaea overgrowth)

• Hydrogen sulfide (newly added 2024)

Why this matters for leaky gut:SIBO (Small Intestinal Bacterial Overgrowth) is a MAJOR cause of intestinal permeability. Treating SIBO often resolves leaky gut.

Connection:

• Bacteria overgrow in small intestine where they don't belong

• They damage the gut lining

• They trigger zonulin release

• Tight junctions loosen

• Leaky gut develops

  
  

If you have digestive symptoms + suspected leaky gut, test for SIBO first.

4. Food Sensitivity Testing (IgG)

Controversial but potentially useful:

• Tests IgG antibodies to common foods

• High IgG suggests food particles are crossing gut barrier (leaky gut)

• Can guide elimination diet

Limitations:

• IgG antibodies are normal — everyone has them

• Doesn't definitively prove leaky gut

• Can have false positives

Use as a tool, not a diagnosis.

5. Symptom-Based Assessment (No Testing)

The pragmatic approach:

If you have:

• Multiple unexplained symptoms

• Autoimmune disease

• Chronic digestive issues

• Food sensitivities that developed suddenly

• Skin problems + gut problems

  
  

Assume leaky gut may be involved and start the healing protocol.

Track improvements:

• Symptom journal

• Energy levels

• Digestive function

• Skin clarity

• Mood stability

• Autoimmune markers (if applicable)

If symptoms improve on the protocol, that's your "test."

Most functional medicine doctors now recommend this approach over expensive testing.

The SIBO-Leaky Gut Connection: Why This Matters

SIBO (Small Intestinal Bacterial Overgrowth) is one of the most common causes of leaky gut — yet it's often missed.

What is SIBO?

Bacteria belong in your colon (large intestine). In SIBO, bacteria migrate backward into your small intestine where they don't belong.

Result:

• Bacteria ferment food in the small intestine (causing gas, bloating)

• Bacteria damage intestinal lining

• Bacteria trigger inflammation

• Tight junctions weaken

• Leaky gut develops

  
  

SIBO Symptoms That Overlap with Leaky Gut:

• Bloating (especially after eating carbs or fiber)

• Gas and belching

• Diarrhea and/or constipation

• Food sensitivities

• Nutrient deficiencies (despite good diet)

• Fatigue and brain fog

• Skin issues

Key difference: SIBO symptoms often worsen with fiber, prebiotics, and fermented foods (which normally help leaky gut). If these worsen your symptoms, suspect SIBO.

How SIBO Causes Leaky Gut:

1. Bacterial endotoxins (LPS) damage intestinal cells

2. Chronic inflammation weakens tight junctions

3. Bacterial enzymes degrade mucus layer

4. Dysbiosis (wrong bacteria in wrong place) disrupts gut barrier

5. Bile acid deconjugation (bacteria break down bile salts, causing fat malabsorption and intestinal damage)

   
   

Why You Should Test for SIBO If Leaky Gut Protocol Doesn't Work:

Standard leaky gut protocols include:

• Probiotics

• Prebiotics

• Fermented foods

• High fiber

But if you have SIBO, these make it WORSE.

Signs you might have SIBO:

• Leaky gut protocol makes you feel worse

• Bloating increases with probiotics

• Fiber causes severe gas/bloating

• Symptoms worse after eating FODMAPs (fermentable carbs)

Solution: Test for SIBO, treat SIBO first, THEN heal leaky gut.

SIBO Treatment (Then Leaky Gut Heals Naturally):

Phase 1: Eradicate Overgrowth

• Herbal antimicrobials: Oregano oil, berberine, neem, allicin

• Prescription antibiotics: Rifaximin (if severe)

• Elemental diet: 2-3 weeks (highly effective but difficult)

Phase 2: Restore Motility

• Prokinetics: Ginger, MotilPro, low-dose naltrexone

• Prevents SIBO relapse

Phase 3: Rebuild Gut Barrier

• NOW follow standard leaky gut protocol

• L-glutamine, zinc, polyphenols, probiotics

• This works because bacteria are gone

80% of SIBO patients who treat the overgrowth see leaky gut symptoms resolve.

Conditions Linked to Leaky Gut (Expanded List)

Research continues to link intestinal permeability to numerous conditions:

Autoimmune Diseases

• Celiac disease (proven link)

• Type 1 diabetes (zonulin elevated)

• Rheumatoid arthritis

• Hashimoto's thyroiditis

• Lupus (SLE)

• Multiple sclerosis

• Inflammatory bowel disease (Crohn's, ulcerative colitis)

• Psoriasis and psoriatic arthritis

  
  

Metabolic Conditions

• Obesity

• Insulin resistance / Type 2 diabetes

• Non-alcoholic fatty liver disease (NAFLD)

• Metabolic syndrome

  
  

Neurological & Mental Health

• Depression and anxiety (gut-brain axis)

• Autism spectrum disorder

• ADHD

• Alzheimer's disease (neuroinflammation link)

• Migraine headaches

• Brain fog / cognitive dysfunction

  
  

Skin Conditions

• Eczema / Atopic dermatitis

• Acne (inflammatory type)

• Rosacea

• Psoriasis

• Urticaria (chronic hives)

  
  

Digestive Disorders

• IBS (Irritable Bowel Syndrome)

• SIBO

• Candida overgrowth

• Food allergies and sensitivities

  
  

Other Conditions

• Chronic fatigue syndrome

• Fibromyalgia

• Asthma and allergies

• Joint pain and arthritis

• Chronic infections (immune dysfunction)

  
  

Important caveat:Association doesn't prove causation. Leaky gut may be a consequence of these conditions (from inflammation) rather than the cause. Or it may be bidirectional — a vicious cycle.

Either way, healing the gut barrier helps.

The Bottom Line on Testing:

2026 Recommendation:

1. Don't rely solely on zonulin tests — they're not accurate enough

2. If you want testing: Comprehensive stool analysis + SIBO breath test

3. For most people: Skip expensive testing, start the healing protocol, track symptoms

4. If protocol doesn't work: Then test for SIBO, infections, or other root causes

The goal is healing, not just testing.

Add These to Your Product Recommendations:

For SIBO Support:

• Antimicrobial herbs: Oregano oil, berberine, neem

• Prokinetics: Ginger, MotilPro

• Low-FODMAP juice options (for active SIBO phase)

  
  

For Post-SIBO Gut Repair:

• All standard leaky gut supplements

• Emphasize polyphenol-rich juice once SIBO is treated

References:

• Dr. Alessio Fasano, zonulin discovery and research

• MaPLE Trial (2021): Polyphenol-rich diet and intestinal permeability

• Institute for Functional Medicine: Intestinal Permeability and Disease

• Research on gut-brain, gut-skin, gut-immune axes

• Studies on L-glutamine, zinc carnosine, and gut barrier healing

• Microbiome research on dysbiosis and tight junction function

• Clinical studies on gluten, stress, NSAIDs and intestinal permeability