In the News, Summer 2023: Reduced Gut Microbiota Diversity Linked to IBS

Research from South Korea found that people with irritable bowel syndrome (IBS) had lower microbial diversity in the gut than healthy individuals. In addition, the relative abundance of 21 bacterial species differed between IBS patients and a healthy control group.

The investigators examined data from 567 adults and children with IBS and 487 controls, from 10 separate data sets (nine shared, publicly available data sets and one of their own), using a unified data processing and analytical approach. They believe that their study, which was published in Microbiology Spectrum, is the first to clearly link IBS and reduced microbiota diversity. Their findings in the pediatric cohort were not statistically significant, but this was attributed to small sample size.

The results suggest that low gut microbiota diversity may predispose people to IBS symptoms, although the study did not establish causality. The researchers noted that low diversity may result from a restricted diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs), which is often adopted by IBS patients to improve symptoms. They conclude that further study is needed to determine whether reduced microbiota diversity actually causes IBS.

Sources: Lower bacterial diversity is associated with irritable bowel syndrome. American Society for Microbiology, January 19, 2023. asm.org/Press-Releases/2023/January/Lower-Bacterial-Diversity-is-Associated-With-Irrit.

Kim G-H, Lee K, Shim JO, Mousa W. Gut bacterial dysbiosis in irritable bowel syndrome: a case-control study and a cross-cohort analysis using publicly available data sets. Microbiology Spectrum, 2023; doi:10.1128/spectrum.02125-22.