Small bowel microbiome offers clues to women's health

This article has been reviewed according to Science X's editorial process and policies . Editors have highlighted the following attributes while ensuring the content's credibility: Credit: Unsplash/CC0 Public Domain A new study by investigators at Cedars-Sinai Health Sciences University has identified differences in the makeup and organization of the small bowel microbiome between women and men. The findings, published in iScience, could offer new insights into why some conditions are more prevalent in women. The small bowel microbiome comprises a community of microorganisms that coexist in this part of the digestive tract and play vital roles in immune function, metabolism and hormonal regulation. "One intriguing finding was a bacterial community containing Granulicatella, which we found only in women," said Ruchi Mathur, MD, director of Clinical Research and Clinical Operations for the Medically Associated Science and Technology (MAST) Program at Cedars-Sinai and corresponding author of the study. "Bacteria in this community appear at increased levels in women with polyendocrine metabolic ovarian syndrome, formerly known as polycystic ovary syndrome." Investigators also found sex differences in how small bowel microbes produce fructans, complex carbohydrates known for triggering digestive symptoms in irritable bowel syndrome (IBS), a condition far more common in women than men. "Our findings show that biological sex is a critical variable in the small bowel microbiome," said Mathur, also a professor of medicine. "We must consider it as we move toward more personalized approaches to understanding and treating disease." Publication details Mohamad Rashid et al, Duodenal microbiome profiles exhibit sex-specific differences, iScience (2026). DOI: 10.1016/j.isci.2026.116679 Journal information: iScience