Association of dietary fibre intake and gut microbiota in adultsOriginal 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 the relationship between dietary fibre intake and gut microbiota composition in adults. Researchers used 16S rRNA gene sequencing to characterize the gut microbiota in faecal samples and calculated energy-adjusted fibre intake from food frequency questionnaires. They evaluated associations between fibre intake and both overall microbial community composition and individual taxon abundance, adjusting for age, sex, race, BMI, and smoking. This work was motivated by evidence that gut microbiota may influence colorectal cancer risk and that diet, particularly fibre, may modify that microbiota.
Who was studied?
The study drew on 151 adults from two independent study populations: the National Cancer Institute (NCI) cohort (n 75) and the New York University (NYU) cohort (n 76). Each population was analyzed separately and then combined in a meta-analysis. The abstract does not provide further demographic detail on these participants beyond the adjustment variables used (age, sex, race, BMI, smoking).
What were the most important findings?
Total fibre intake was significantly associated with overall gut microbial community composition in the NYU population (P=0.008) but not in the NCI population (P=0.81). In the meta-analysis combining both populations, higher fibre intake tended to be associated with greater abundance of several genera within class Clostridia, including SMB53, Lachnospira, and Faecalibacterium (likely reflecting Faecalibacterium prausnitzii, a butyrate-producing, anti-inflammatory commensal). Higher fibre intake was also associated with lower abundance of Actinomyces, Odoribacter, and Oscillospira.
What are the greatest implications of this study?
The findings suggest that dietary fibre intake is linked to specific shifts in gut microbiota composition, particularly favoring Clostridia genera such as Faecalibacterium that are associated with butyrate production and anti-inflammatory activity. Because gut microbiota composition may in turn influence colorectal cancer risk, these fibre-associated microbial shifts could represent one pathway by which diet affects cancer risk. The inconsistent association with overall community composition across the two study populations also highlights the need for further research to clarify how consistently fibre intake shapes the gut microbiome across different populations.