Primary Causes & Action Plans

hs-CRP

Systemic inflammation reflecting intestinal barrier breakdown
hs-CRP elevation reflects systemic inflammation triggered by bacterial toxins leaking through damaged intestinal barriers. While many conditions raise hs-CRP, a high level in conjunction with GI symptoms strongly suggests leaky gut.
Target < 1.0 mg/L
Suggested Action Plan

Reduce hs-CRP by healing gut integrity: eliminate triggering foods (gluten, dairy, processed foods), take bone broth, L-glutamine, and zinc carnosine to repair the intestinal lining.

Zonulin

Directly measures intestinal permeability; elevated zonulin = leaky gut
Zonulin is a protein produced by intestinal cells that regulates tight junction permeability. Elevated zonulin directly indicates increased intestinal permeability (leaky gut). Gluten, lipopolysaccharides, and dysbiosis all elevate zonulin.
Target < 70 ng/mL (normal)
Suggested Action Plan

Lower zonulin by eliminating gluten (if sensitive), restoring beneficial bacteria through probiotics and fermented foods, and taking L-glutamine and zinc carnosine. Retest in 2-3 months.

IgA (Secretory Immunoglobulin A)

First-line immune defense in the gut; low IgA impairs barrier function
Secretory IgA is your immune system's primary defense against pathogens in the GI tract. Low IgA indicates immune dysregulation and impaired barrier protection, allowing pathogens and toxins to cross. Chronic stress and infection deplete IgA.
Target > 200-400 mg/dL (fecal reference)
Suggested Action Plan

Restore IgA through stress management, adequate sleep, probiotics (especially Lactobacillus and Bifidobacterium), and prebiotic fiber. Bone broth and colostrum also support IgA production.

Vitamin D

Critical for tight junction integrity and immune tolerance
Vitamin D is essential for maintaining intestinal tight junction proteins and promoting regulatory T cells (immune tolerance). Deficiency allows intestinal permeability to increase and promotes food sensitivities.
Target > 50 ng/mL
Suggested Action Plan

If deficient, supplement vitamin D3 4000-5000 IU daily plus 20-30 minutes of midday sun 3-4 times per week. Retest in 8-12 weeks. Once optimal, maintain with 2000-3000 IU daily.

Ferritin

Low iron impairs tight junction integrity and increases infection risk
Iron is essential for tight junction protein synthesis and immune function. Iron deficiency increases intestinal permeability and pathogenic bacterial overgrowth, perpetuating leaky gut.
Target 50-150 ng/mL
Suggested Action Plan

If ferritin is low, supplement with iron glycinate 25 mg daily (absorbs better than ferrous sulfate). Take with vitamin C for absorption, separate from coffee/tea. Retest in 8-12 weeks.

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Getting Started

1
Test Your Intestinal Barrier Integrity

Order zonulin, hs-CRP, fecal IgA, vitamin D, and ferritin. These biomarkers reveal whether leaky gut is present and what's contributing to it (inflammation, nutrient deficiency, dysbiosis).

2
Eliminate Gut-Damaging Foods

Start an elimination diet: remove gluten, dairy, processed foods, and seed oils for 4-6 weeks. These foods damage tight junctions and trigger inflammation. Reintroduce foods one at a time after healing, testing for reactions.

3
Repair the Intestinal Lining

Take L-glutamine (3-5g daily), zinc carnosine (75 mg twice daily), bone broth, and slippery elm. These nutrients directly repair intestinal epithelial damage. Healing takes 3-6 months.

4
Restore Beneficial Bacteria

Take a multi-strain probiotic (Lactobacillus, Bifidobacterium). Eat fermented foods: sauerkraut, kimchi, tempeh, kefir. Increase prebiotic fiber: inulin, FOS, resistant starch. Healthy bacteria prevent pathogenic overgrowth.

5
Retest in 3 Months

Zonulin, hs-CRP, and IgA should improve within 3 months of comprehensive gut healing. Retest to confirm improvement and identify any remaining issues.

Why I built this guide.

"Leaky gut is real and treatable. Sealing your intestinal barrier can resolve chronic inflammation and food sensitivities."

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