Mixed

A low FODMAP diet significantly reduces total colonic bacterial abundance and increases faecal pH compared to a typical high-FODMAP diet, despite maintaining similar short-chain fatty acid concentrations.

If you are on a low FODMAP diet for IBS, be aware that it significantly reduces the total number of bacteria in your gut compared to a normal diet. While this doesn't necessarily change the amount of beneficial short-chain fatty acids produced, it does alter which bacteria are present. To mitigate this, ensure you are getting enough fiber (like psyllium or resistant starch) and consider liberalizing your FODMAP intake to the minimum amount needed to control symptoms, rather than restricting indefinitely, to support a healthier microbiome structure.