Leaky gut syndrome is a proposed digestive condition where the intestinal lining allows bacteria and toxins into the bloodstream. It refers to an increase in permeability of the intestinal lining, which could play a role in Crohn’s and other diseases.

Many doctors and healthcare professionals do not recognize leaky gut syndrome (LGS) as a diagnosable condition. However, further research into the area may help doctors to better understand the mechanisms and implications in humans.

Some theorize that in leaky gut syndrome, gaps in the intestinal walls allow bacteria and other toxins to pass into the bloodstream.

In this article, we discuss LGS, as well as its proposed symptoms, causes, and risk factors.

Image depicting leaky gut syndromeShare on Pinterest
Image depicting leaky gut syndrome

Digestive enzymes in the stomach and small intestine break down nutrients in food and drink into smaller molecules that the body uses for energy, growth, and repair.

Tight openings in the intestinal walls allow water and nutrients to pass through into the bloodstream while keeping harmful substances inside. The rate of this passing is known as intestinal permeability (IP).

People often refer to a chronic increase in IP as LGS. When this occurs food particles, bacteria, and toxins to enter directly into the bloodstream. However, more research is necessary to understand the full implications of this in humans.

Gut microbiota and leaky gut syndrome

The intestines are also home to a wide range of bacteria called gut microbiota. These bacteria aid digestion, protect the intestinal wall, and support immune function.

Imbalanced in gut microbiota can impact the overall health of the intestine, including permeability.

For example, imbalances in the gut microbiota can trigger the body’s immune response, causing inflammation and increased IP.

These factors may lead to LGS.

A chronic increase in IP may contribute to several health conditions, such as:

However, a 2015 review article suggests that increased IP may contribute to the development of inflammatory bowel disease (IBD). A separate 2019 review shows evidence of IP occurring before the onset of type 1 diabetes.

Scientists have also been investigating the gut-brain axis. This is the relationship between the GI tract and the brain. A 2017 review suggests that leaky gut may contribute to mental health conditions, such as anxiety and depression. However, scientists need to carry out further research to support this claim.

Many proposed LGS symptoms are similar to other health conditions. This can make the condition difficult for doctors to identify.

LGS may cause or contribute to the following symptoms:

There are no definable causes of leaky gut syndrome. However, various risk factors can disrupt the gut microbiota and contribute to increased IP in general. Examples include:

Autistic children often develop significant digestive problems, such as constipation, diarrhea, and vomiting.

However, there is no conclusive proof to support claims that LGS plays a role in any of these conditions.

Gut microbiota and autism

In a 2019 review, researchers confirmed an association between gut microbiota imbalances and autism.

In a small 2017 study, researchers compared stool samples from two groups of children — autistic children with GI symptoms, and those without autism or GI symptoms. The researchers identified significantly higher amounts of Clostridium perfringens bacteria in samples collected from autistic children with GI symptoms.

However, the direction of association between gut microbiota and autism is unclear.

Leaky gut syndrome is a proposed intestinal condition in which a weakening of the intestinal walls allows bacteria and toxins into the bloodstream.

Many medical professionals do not recognize LGS as a diagnosable condition, and more research is necessary to understand the mechanisms and implications in humans.

Read this article in Spanish.