Leaky Gut: The Complete Guide

Gutter • Mar 3, 2026 • 10 min read

Intestinal permeability (leaky gut) is when the gut lining allows undigested food, toxins, and bacteria to pass into the bloodstream. Understanding the mechanisms helps guide repair.

Quick Answer

"Leaky gut" is a simplified term for intestinal permeability — when tight junctions between gut lining cells loosen, allowing substances to pass that shouldn't. It's now recognized in mainstream research as a legitimate condition.

What Is Leaky Gut (Really)

Your gut lining is a single layer of cells with tight junctions between them. These junctions control what passes through. When they loosen:

  • Undigested food particles enter bloodstream
  • Immune system reacts
  • Inflammation increases systemically

The Real Story

This isn't alternative medicine anymore. Research has validated intestinal permeability as measurable and clinically relevant. Key research: zonulin pathway discovered by Dr. Alessio Fasano.

Why It's So Dangerous

The gut lining is the barrier between the outside world and your bloodstream. When compromised:

  • Immune activation increases
  • Chronic inflammation develops
  • Food sensitivities multiply
  • Systemic symptoms emerge (fatigue, brain fog, joint pain)

Common Causes

  • Chronic stress
  • Alcohol excess
  • NSAID overuse
  • Dysbiosis/SIBO
  • Processed food diet
  • Infections

Testing Options

  • Lactulose-Mannitol test: Direct permeability measurement
  • Zonulin: Indirect marker (use as secondary clue)
  • Comprehensive stool panel: Assess inflammation and microbiome

Repair Protocol

  • Remove triggers (alcohol, NSAIDs, inflammatory foods)
  • Support lining repair (zinc carnosine, L-glutamine, butyrate)
  • Address underlying causes (SIBO, dysbiosis, stress)
  • Support microbiome (appropriate probiotics, prebiotics)

Key Takeaways

  • Leaky gut is real and measurable
  • It's a barrier problem that creates systemic issues
  • Repair requires removing triggers and supporting healing
  • Work with a clinician for comprehensive approach

Educational only, not medical advice. Work with a qualified clinician for diagnosis and treatment.