Does a Leaky Gut Increase Your Risk of Diabetes? Here's What a Gastroenterologist Says

Having “leaky gut syndrome” makes it sound as if your gastrointestinal system is dripping like a faucet. While that’s not quite correct, it does give you an image of what may be going on inside your body. Leaky gut is the term for a condition where the lining of the small intestine becomes damaged. As a result, undigested food particles, harmful pathogens and toxins can gain entry into the bloodstream.

Also called increased gut permeability, leaky gut is associated with GI conditions, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), as well as heart disease and obesity, according to a review in Molecules in 2023.

There is also growing research that links leaky gut to type 2 diabetes. So, what’s going on? We spoke with a gastroenterologist and a dietitian to talk about what leaky gut is, the connection to type 2 diabetes, and how to manage your blood sugar and improve your gut health.

What Is Leaky Gut?

The gut is a well-controlled system. “Under normal conditions, the walls of the inside of your small intestine are lined with cells that literally act like guards. Their job is to stand side-by-side, shoulders touching, and not allow anything into your bloodstream unless your body needs it,” explains Emily Spurlock, a registered dietitian who specializes in gut health.

For any number of reasons, the gut lining can be damaged. As a result, gaps emerge in the gut barrier, allowing large proteins, undigested particles, pathogens and toxins through, says Spurlock. This barrier breakthrough can affect your health in a number of ways, including disrupting hormonal, immune, nervous, respiratory or reproductive function, notes the aforementioned review in Molecules. 

Signs and Symptoms of a Leaky Gut

Leaky gut may be associated with IBD and IBS—so having chronic gut problems or fatigue may be symptoms of the syndrome. However, it’s not that straightforward and, in fact, it could be challenging to find out if you have a leaky gut or not, according to Ibrahim Hanouneh, M.D., a gastroenterologist at MNGI Digestive Health in Eagan, Minnesota.

Hanouneh explains that typical signs and symptoms of a leaky gut could include acute or chronic diarrhea, constipation, bloating, food sensitivities, fatigue, headaches, joint pain or stiffness. Still, symptoms alone are not enough information to say you have a leaky gut, since they’re often symptoms of many other health conditions, he says.

What’s more, leaky gut syndrome is not recognized by all health care providers, says Hanouneh. (The Cleveland Clinic calls it a theory and a hypothetical condition, and right now there are no validated tests to diagnose leaky gut.) It’s important to talk to your health care provider if you’re concerned that you may be experiencing a leaky gut. 

Gut Health and Type 2 Diabetes—What’s the Link Between the Two?

Growing evidence suggests there could be a link between gut health and the development and progression of type 2 diabetes. More specifically, this has to do with the balance of your microbiome, or the trillions of microorganisms that live inside your gut.

Since the gut acts as a barrier and filters what gets absorbed into the bloodstream and the surrounding area, the type of bacteria in the gut matters. “If the gut microbiome is out of balance or there is an overgrowth of [the bad] bacteria in the small intestine, this could [also] lead to inflammation and irritation to the lining of the gut,” Spurlock says.

A study in Endocrinology Connect in 2021 found that people with type 2 diabetes had a lower diversity of gut bacteria, as well as a higher concentration of bacteria that degrade mucus, which provides an important layer of protection in the intestines. In addition, they had less bacteria that produce short-chain fatty acids, which are responsible for fermenting fiber, lowering inflammation and improving gut barrier integrity. Short-chain fatty acids may also impact insulin sensitivity and glucose metabolism, says Hanouneh.

While having diabetes doesn't necessarily mean having a leaky gut, consistently having high blood sugars (hyperglycemia) could promote gut inflammation, which may impact the health of your microbiome and overall GI system.

Tips to Manage Leaky Gut and Diabetes

Focus on High-Fiber Foods

Hanouneh recommends a diet rich in vegetables, fruits, legumes and whole grains. These foods contain fiber and may promote the growth of beneficial bacteria, encourage the production of short-chain fatty acids in the gut and strengthen the gut barrier, according to the review in Molecules.

Minimize the Intake of Added Sugars and Refined Carbs

Limit foods high in added sugars, as well as simple and refined carbohydrates. Consuming too much of these foods spikes blood sugar levels and could also interrupt the gut microbiome. How? When broken down during digestion, these foods provide fuel for harmful gut bacteria, which can ultimately cause inflammation and irritation in the gut lining, Spurlock explains.

Follow the Diabetes Plate Method

Following the Diabetes Plate Method from the American Diabetes Association can help keep your blood sugar levels within range. This method recommends filling half your plate with nonstarchy vegetables, one-quarter with carbohydrate foods like whole grains or starchy veggies, and one-quarter with lean protein.

Focus On Foods That Don’t Aggravate Symptoms

Most importantly, the symptoms of a leaky gut vary from person to person. You may notice that certain foods don’t digest well and trigger gas and bloating, while the same food may have no impact on someone else.

All that to say, there isn’t one diet that fits everyone, and recognizing which foods cause discomfort could improve your quality of life. This is the time to speak with a gastroenterologist or registered dietitian to discuss your symptoms and explore a balanced and nutritious meal pattern that meets your health needs.

Before coming up with a plan, your gastroenterologist or dietitian may help you to identify foods that cause symptoms by asking you to follow an elimination diet, such as dairy-free, gluten-free or low-FODMAP, before reintroducing specific foods to your diet one at a time to determine your tolerance.

Bottom Line

While the scientific community continues to broaden our understanding of leaky gut syndrome, it is important to remember that following a balanced and nutritious meal pattern could help maintain a stable blood sugar level and a healthy gut and lower the risk of inflammation.

Some foods may exacerbate unpleasant digestive symptoms, especially if you already have an inflamed gut. See your health care provider and registered dietitian to discuss your signs and symptoms. Most importantly, diet is only one aspect of diabetes management—being active, managing stress and getting good sleep are also a part of keeping blood sugars under control.