A new study has found that a low FODMAP diet not only helps reduce symptoms in people with irritable bowel syndrome with diarrhea (IBS-D), but may also improve the condition known as “leaky gut.”
This is the first time researchers have shown that this type of diet could improve the health of the intestinal lining and calm down certain immune system responses in IBS patients.
The results were published in the journal Gastroenterology and mark a major step forward in understanding how food affects gut health. The study was led by Dr. Prashant Singh, a gastroenterologist at Michigan Medicine.
According to Dr. Singh, scientists already believed that diet and gut bacteria were connected to leaky gut, but they didn’t know exactly how. This study shows how food can impact the gut’s immune system and gut barrier, helping us better understand why certain foods can cause problems.
Leaky gut, also known as colonic barrier dysfunction, happens when the intestinal lining becomes more permeable than it should be. This can allow harmful substances, like bacterial toxins, to pass through the gut wall into the body.
In people with IBS, this can lead to pain and other digestive problems. Mast cells, which are a type of immune cell found in the gut, are thought to play a role in this process by becoming overactive and contributing to inflammation.
To study how diet might help, researchers put 48 patients with IBS-D on a low FODMAP diet for four weeks. FODMAPs are certain types of carbohydrates that are hard to digest and can trigger symptoms in people with IBS.
Participants were given specially prepared meals for the duration of the study. Out of the 42 patients who completed the trial, 34 responded well to the diet. These individuals experienced less diarrhea and abdominal pain.
The researchers examined changes in gut barrier function and mast cell activity before and after the diet. They found that the low FODMAP diet led to improvements in gut barrier health and a reduction in the number and activation of mast cells in the colon.
This is important because fewer active mast cells means less inflammation and fewer symptoms.
To better understand why this happens, the research team also studied mice that were treated with stool samples from the human participants. They found that people eating a high FODMAP diet had higher levels of lipopolysaccharides (LPS), which are substances made by gut bacteria.
LPS can leak through the gut wall and trigger immune responses by activating mast cells, making the gut even leakier. This creates a cycle of inflammation and gut damage. The low FODMAP diet seemed to break this cycle.
Given the results, the researchers suggest that doctors consider using mast cell stabilizers alongside the low FODMAP diet to improve treatment or as an alternative when the diet is not suitable for a patient.
Dr. Singh noted, “Our study shows diet is not a quick fix—it’s a real solution for some patients with IBS.” The team hopes future research will include more patients, including those who don’t respond to the diet, and look at different types of IBS, not just IBS-D.
If you care about gut health, please read studies about how high blood pressure medicine might affect your gut and origin of Parkinson’s disease is in the gut.
For more about gut health, please read studies that your gut can help lower your blood pressure: here’s how and from shock to awe: a zap in the gut could be the new insulin for people with diabetes.
The study is published in Gastroenterology.
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