What Is Leaky Gut Syndrome? Experts Weigh in on the Causes and Symptoms

There are a lot of things that can go wrong with your gut, leading to serious discomfort on your part. Gas, bloating, diarrhea…no one wants to deal with that. But if your doctor has ruled out conditions like irritable bowel syndrome, food intolerances, and other common issues, you may wonder if you could be dealing with leaky gut syndrome.

It's important to state this upfront: There's a lot of controversy around leaky gut syndrome, and plenty of basic questions swirling around it like, "what is leaky gut syndrome?" and "is leaky gut real?" The answers are a little more complicated than they are for other well-known conditions. After all, while leaky gut syndrome has been studied, there aren't clear-cut answers around this condition.

Still, plenty of people swear they've experienced leaky gut syndrome. If you're having leaky gut syndrome symptoms, it's understandable to wonder about how leaky gut syndrome is diagnosed and leaky gut treatment plans.

Here's what we know about leaky gut syndrome, based on research, along with input from experts on what to do if you're having gastrointestinal issues and don't know what's causing them.

The medical community does not consider leaky gut to be a medical condition. Instead, it's referred to as a "hypothetical condition" based on the concept of intestinal permeability (more on that in a second).

Doctors practice based on research-based evidence, and there isn't evidence to support that leaky gut is real, says Ashkan Farhadi, MD a gastroenterologist and intestinal permeability researcher at MemorialCare Orange Coast Medical Center in Fountain Valley, Calif. "Leaky gut syndrome is like a wish list from people who want to create a disease," he says.

"There's ongoing research into intestinal permeability and its potential links to various health issues, but the concept of leaky gut as a standalone syndrome remains controversial and hypothetical," says Scott Keatley, RD, co-owner of Keatley MNT.

The concept of leaky gut syndrome is based off of intestinal permeability, which is a real thing. Everyone's intestine is permeable to some extent, which means that liquids and gasses pass through, Dr. Farhadi explains. The mucosal lining of your intestines absorbs water and nutrients from the food you eat into your bloodstream, but some people have guts that let more water and nutrients through.

Your intestinal lining is also designed to put up a barrier against bacteria and other pathogens inside your gut, which is part of your immune system, Dr. Farhadi explains. Research has shown that people with certain gastrointestinal diseases have a higher degree of intestinal leakage and let larger molecules in.

"The premise of leaky gut is that the permeability has been increased to the point that bad stuff gets in," Dr. Farhadi says. "But intestinal permeability is dynamic — it's not a fixed phenomenon."

Because so many things permeate the gut and different variables can impact this, "it's difficult to tell what is normal and what is not," Dr. Farhadi says.

Erica Zellner, MS, LDN, a certified nutrition specialist at Parsley Health, describes leaky gut syndrome this way: "In a healthy individual, our gut lining has very small gaps, called tight junctions, that allow nutrients, water, etc. through and block larger molecules from passing into the bloodstream. When a person has 'leaky gut,' those tight junctions can become loose, which can allow larger food particles, bacteria, and toxins into the bloodstream."

The theory of leaky gut syndrome is that intestinal permeability has an underlying cause that happens independently of a GI disease, Dr. Farhadi says. Potential causes have been listed as having conditions like celiac disease, overusing alcohol or non-steroidal anti-inflammatory drugs (NSAIDs), and stress, Zellner says.

"While increased intestinal permeability is associated with certain autoimmune diseases and conditions like celiac disease and Crohn's disease, the relationship is complex and not really understood," Keatley says. "The human gut is naturally permeable to allow nutrient absorption, and its permeability can be influenced by various factors."

Because leaky gut syndrome isn't a recognized medical condition, it's difficult to have an exact list of symptoms. However, Jessica Cording, RD, nutritionist and the author of "The Little Book of Game-Changers", says these symptoms are typically associated with the syndrome:

There is no test to determine if someone has a leaky gut, Dr. Farhadi says. Instead, it may be what people land on when they can't figure out why they're having certain symptoms.

"Leaky gut is often used as a catch-all diagnosis when there are questions remaining about symptoms," Cording says. "But while you will see different opinions on whether this is 'real' or not, the important thing to keep in mind is that the symptoms that someone experiences are very real."

There is no set treatment for leaky gut, but healthcare providers may recommend treating the symptoms. That can include taking probiotics to try to support the good bacteria in your gut and altering your diet, Cording says.

There is no leaky gut diet. However, if you have uncomfortable gastrointestinal symptoms, your doctor may recommend that you go on an elimination diet, where you weed out certain foods and slowly re-introduce them to see how you feel, per Cording. Common things you might see taken out are gluten and dairy, she explains.

Healthcare providers will also often recommend that you limit alcohol, which is a known gastrointestinal irritant, as well as minimizing processed and high-sugar foods, Cording says.

There are no set signs that leaky gut is healing, other than you'll gradually start to feel better. "'I feel more like myself again' is a phrase I've heard from clients over the years," Cording says.

Zellner says that signs of the condition will start to diminish, too. "Gas, bloating, discomfort, and constipation should begin to dissipate or resolve completely," she tells POPSUGAR. "You may also notice food sensitivities are healing. If you had skin or cognitive symptoms, those should begin to heal as well."

Other signs can include improved bowel movement regularity, and just feeling more resilient, she says. "It is very, very individual, though," Cording says. "That's one of the things I can't stress enough."