10 Signs You Have Leaky Gut Syndrome (And What to Do)

"Leaky gut" gets thrown around a lot, and it's worth noting upfront: increased intestinal permeability is a recognised, measurable phenomenon in research, but "leaky gut syndrome" as a standalone diagnosis remains debated within mainstream medicine. That doesn't mean the underlying symptoms aren't real or worth addressing — it means the label is less important than paying attention to the pattern of signs below.

1. Chronic Bloating and Gas

Persistent bloating that isn't clearly tied to specific foods can indicate that undigested particles are triggering an inflammatory response in the gut lining.

2. New or Worsening Food Sensitivities

When the gut lining's tight junctions are compromised, partially digested food particles can enter the bloodstream, triggering immune responses to foods that never used to cause problems.

3. Fatigue and Brain Fog

Chronic low-grade inflammation originating in the gut has been linked to fatigue and difficulty concentrating, independent of sleep quality.

4. Skin Issues Like Eczema or Acne

The gut-skin axis means inflammatory compounds that leak from a compromised gut lining can show up as skin flare-ups, particularly eczema, acne, and rosacea.

5. Joint Pain

Some research links systemic inflammation from gut permeability to joint discomfort, particularly in people who don't have a clear injury or arthritis diagnosis explaining the pain.

6. Autoimmune-Type Flare-Ups

Several autoimmune conditions have been associated with increased intestinal permeability in research, though the exact cause-and-effect relationship is still being studied.

7. Seasonal Allergies Getting Worse

An overactive immune response driven by gut inflammation can lower your threshold for reacting to environmental allergens.

8. Sugar and Carb Cravings

An imbalanced gut microbiome can influence cravings more than willpower does — certain bacteria thrive on sugar and can drive cravings for the foods that feed them.

9. Irregular Digestion

Alternating constipation and diarrhoea, without a clear dietary trigger, is a common pattern reported alongside gut lining issues.

10. Mood Changes

Given the gut-brain connection, inflammation originating in the gut can contribute to low mood or increased anxiety in some people.

How Many Signs Are "Too Many"?

Experiencing one or two of these signs occasionally is common and not necessarily cause for concern. It's the combination and persistence that matters — several of these signs occurring together, consistently, over weeks or months, is a stronger signal worth investigating than any single symptom in isolation.

The Zonulin Connection

Zonulin is a protein that regulates the tight junctions between cells in your gut lining, essentially controlling how "open" or "closed" your gut barrier is. Research has found elevated zonulin levels associated with several autoimmune and inflammatory conditions, giving researchers a measurable marker to study what was previously a harder-to-quantify concept — though testing for zonulin isn't yet a standard, widely available clinical test in Australia.

What Causes Leaky Gut?

Chronic stress, a diet high in processed foods and low in fibre, excessive alcohol, certain medications (particularly long-term NSAID use), and undiagnosed food intolerances are among the most commonly cited contributors.

What to Do About It

Increasing dietary fibre and fermented foods, reducing processed food and alcohol intake, and supporting gut lining repair with targeted nutrients like L-glutamine are the most commonly recommended starting points. L-Glutamine is the primary fuel source for the cells lining your intestine and is one of the more evidence-supported supplements specifically for gut lining support.

When to See a Doctor

If you're experiencing several of these signs together, it's worth ruling out other conditions with a GP before assuming it's gut-related — many of these symptoms overlap with thyroid issues, coeliac disease, and other conditions that need proper diagnosis and treatment.

Gut Lining Repair Timeline

Intestinal cells regenerate quickly compared to most tissue in the body, with the cell lining largely replaced every few days. This is encouraging news — it means dietary and supplement changes can begin influencing gut lining health relatively quickly, even though the cumulative, noticeable improvement in symptoms typically takes several weeks as the overall inflammatory pattern settles down alongside the faster cellular turnover.

The Bottom Line

Whatever you call it, a pattern of chronic bloating, food sensitivities, fatigue, and skin issues is worth addressing at the gut level. Diet changes and targeted gut-repair nutrients are a reasonable first step, alongside ruling out other causes with a healthcare professional.