Gut microbiome mediates the associations between lifestyle factors and risk of colorectal high-risk adenoma: results from a population-based cohort studyOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study examined how common lifestyle factors relate to the risk of colorectal high-risk adenomas (HRAs), precursor lesions to colorectal cancer. It focused on whether gut microbiota composition helps explain, or mediates, the connection between lifestyle habits and HRA risk. Researchers combined lifestyle questionnaires with 16S rRNA sequencing of fecal samples, then used multivariate models and causal mediation analysis to link lifestyle exposures, microbial taxa, and HRA outcomes.
Who was studied?
A total of 3,827 participants were enrolled from a multicenter colorectal cancer screening cohort. Within this group, 272 participants had high-risk adenomas and 1,253 served as controls. Lifestyle information covering the 12 months before enrollment was collected via questionnaires, and fecal samples were taken at enrollment for microbiome analysis.
What were the most important findings?
High body mass index, smoking more than 30 pack-years, and drinking more than 4 alcoholic units per week were each identified as independent risk factors for high-risk adenoma. Using MaAsLin2, the researchers found associations between these lifestyle risk factors and specific gut microbial taxa. The abstract does not specify Desulfovibrio, sulfate-reducing bacteria, or hydrogen sulfide among the implicated taxa or pathways.
What are the greatest implications of this study?
The findings suggest that gut microbiota do not merely correlate with colorectal adenoma risk but may actively mediate how obesity, smoking, and heavy alcohol use translate into higher risk of high-risk adenomas. This positions the microbiome as a potential intermediary target for reducing lifestyle-driven colorectal cancer precursor risk. Identifying the specific mediating taxa could inform future screening or prevention strategies aimed at modifying gut microbial composition in high-risk individuals.