Signs of Leaky Gut: What It Is and What You Can Do About It

Harvard Health has called it a medical mystery. It has been linked to gut trouble, autoimmune conditions, and even mental health concerns. I am talking about leaky gut, also called intestinal permeability. Have you heard of it?

Many doctors and much of the established medical community remain cautious about the term, but there is growing research connecting it to a wide range of health conditions. So what exactly is leaky gut? Do you have it? How does it happen, and what can you do about it?

What Is Leaky Gut?

Your gut is not simply a 30 foot muscular tube that starts at your mouth and ends in the bathroom. It is a vast, complex system. It breaks food down into digestible pieces, moves it through your gastrointestinal tract, and skillfully absorbs water and nutrients while keeping harmful substances out. Research increasingly shows these functions are interconnected with the rest of your body, from your heart to your brain.

Your gastrointestinal tract is lined with millions of cells arranged side by side in a single layer, which, if spread flat, would cover about 400 square meters. These cells act as gatekeepers, letting in what your body needs and keeping out the rest. That selective barrier only works when the cells are healthy and tightly joined together through what are called tight junctions.

Leaky gut happens when those tight junctions loosen. The barrier becomes irritated and weakened, tiny gaps appear, and things that should stay out, like food particles, waste products, and bacteria, slip into the bloodstream. Your immune system responds by fighting them off, much like it fights a cold virus, which triggers inflammation. That immune response is normal and protective, but when it happens constantly, it takes a toll.

Do You Have a Leaky Gut?

The symptoms overlap with other digestive conditions like inflammatory bowel disease, celiac disease, and Crohn's disease: diarrhea, constipation, cramping, bloating, food sensitivities, and nutrient deficiencies.

Because the particles absorbed into the bloodstream travel throughout the body, symptoms can show up almost anywhere. Research links leaky gut to fatigue, headaches, brain fog, difficulty concentrating, joint pain, and skin issues like acne, rashes, and eczema. It has also been associated with diabetes, polycystic ovarian syndrome, liver disease, chronic fatigue syndrome, and autoimmune conditions like lupus and multiple sclerosis, with possible links to anxiety and depression as well.

Many of these conditions are tied to chronic inflammation, though more research is needed to fully understand the connections. And even with symptoms present, leaky gut is genuinely difficult to evaluate. There are some biomarker tests, but no single reliable diagnostic tool exists yet, so it is hard to say definitively whether your symptoms stem from a leaky gut or whether the leaky gut itself is a symptom of something else.

What Causes Leaky Gut

It is not fully clear what causes the tight junctions to loosen, and researchers are still working out how the gut barrier functions. Genetics may play a role, along with certain medications and gut infections. A diet low in fiber, adults should aim for 25 to 30 grams a day, is also linked to leaky gut, as is a diet high in added sugar and saturated fat. Chronic stress and an imbalance in your gut microbes may contribute as well. And as you age, your cells, including the ones lining your gut, become more vulnerable to damage and slower to heal, which can leave the barrier more susceptible to loosening.

What You Can Do About It

The most effective approach is addressing inflammation through a more gut-friendly diet. That means cutting back on alcohol and processed foods high in fat, sugar, or artificial sweeteners, and avoiding any foods you know you are sensitive or allergic to. If you have diagnosed celiac disease, staying away from gluten entirely is essential, since exposure can trigger a significant inflammatory response.

In their place, build meals around plant-based probiotics and fiber, which feeds your friendly gut microbes:

• Plant-based fermented foods: coconut or oat milk yogurt, kimchi, sauerkraut, miso, and tempeh
• Fruits and vegetables: berries, oranges, broccoli, carrots, and zucchini
• Nuts and seeds: walnuts, cashews, and chia seeds
• Whole grains: oats, corn, and quinoa

If you plan to increase your fiber intake, do it gradually over several days or weeks. Sudden increases can cause gas, bloating, and discomfort, and if you have IBS, it is worth talking with your doctor or with me about which fibers are right for you.

Regular movement supports digestion too. Even a 15 to 20 minute walk after eating can help. And do not overlook stress management, quality sleep, and avoiding smoking, all of which matter for your gut and for the rest of your body. If you make changes, keeping a simple journal can help you track whether your symptoms are improving.

Final Thoughts

A few simple shifts toward a gut-friendly, plant-forward diet can go a long way in supporting a healthy gut lining. Leaky gut is associated with both gut and non-gut symptoms, it is an inflammatory condition linked to metabolic patterns, autoimmune conditions, and mental health, and there is still no single definitive diagnostic test for it. This remains a fairly new area of research, so expect to see more information emerge over time.

In the meantime, if your symptoms suggest a leaky gut, moving toward a more plant-forward, fiber-rich, probiotic-rich diet, along with regular movement, stress management, and quality sleep, is a solid place to start.

If leaky gut or other inflammatory symptoms are bothering you, I would love to help you get to the root of it.

Written by

Dr. Naija, Doctor of Functional Medicine, PhD

Dr. Naija is a Doctor of Functional Medicine, Board-Certified Holistic Nutritionist, Certified Herbalist, and chef with more than 20 years of culinary expertise. She is the founder of The Naija Goddess Center for Culinary Medicine, where she connects functional health insight with practical food and lifestyle strategy.