Some of your gut bacteria—especially the beneficial Bifidobacteria—produce an important short-chain fatty acid (SCFA) called butyrate. They do this by fermenting fiber in the digestive tract. Butyrate acts as a food for the cells of the intestinal lining, helping to maintain the integrity of this one-cell-thick layer that separates the digestive system from the rest of the body. A recent study in the journal Nature found that butyrate acts as a switch that programs the immune system to produce important cells—regulatory T cells (T reg cells for short).

That may not sound like much, or may sound like a foreign language to you, but I want you to understand the vital role regulatory T cells play in our immune function. T reg cells help to balance your immune system by helping your immune system tolerate certain foreign particles rather than mounting an unnecessary immune response that could end in an autoimmune condition (in which your immune system mistakenly attacks the body’s own tissue/ misidentifying it as a foreign particle). In effect T reg cells help your immune system respond appropriately to that which it encounters—including the food that passes through your digestive tract.

People with inflammatory bowel disease (IBD), which is an autoimmune disease, have been found to lack butyrate-producing bacteria in the gut. In the study, researchers used an animal model of colitis (a form of IBD) and found that the administration of butyrate increased T reg cells and improved colitis symptoms. This shows that not only is butyrate important in maintaining a healthy intestinal lining, but also in immune function.

The production of butyrate is just one of numerous ways in which beneficial gut bacteria help balance the immune system. Achieving and maintaining gut balance is vital for digestive and overall health.