How could diet affect IBS?

    Written by:
    Brady Holmer

    Fact-checked

    by:

    Nick Milazzo, Shyam Jayaraman
    Last Updated: May 16, 2025

    Diet can significantly affect irritable bowel syndrome (IBS) by influencing gut fermentation and gas production, which may exacerbate symptoms like abdominal pain and diarrhea. Implementing a low-FODMAP diet and following traditional dietary advice can help alleviate diarrhea-predominant IBS symptoms.

    Many soluble fibers can be fermented by gut microbes to produce energy, resulting in by-products such as short-chain fatty acids and gas. The combination of fermentability and solubility can lead to accumulated gas and water retention in the colon, which can worsen abdominal pain and diarrhea. The low-FODMAP diet has been shown to reduce diarrhea-predominant IBS symptoms, and traditional dietary advice (such as avoiding trigger foods, limiting alcohol, and eating smaller, more frequent meals) is similarly effective.[1]