Structural changes in gut microbiome after Ramadan fasting: a pilot 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 pilot study tested whether Ramadan fasting, a form of time-restricted eating, changes gut microbial composition and diversity. Stool samples were collected before fasting and at the end of Ramadan after 29 days. Researchers built a 16S rRNA amplicon library and sequenced the V4 region on the Illumina MiSeq platform. Microbial community analysis used the QIIME program, with LEfSe and random forest methods to identify the most affected taxa.
Who was studied?
The study enrolled nine adult human subjects, providing paired stool samples before and after Ramadan fasting. The design was a small pilot study with a limited sample size. Participants were healthy volunteers, and the metadata indicate a mix of male and female adults spanning adult to middle age. Each person served as their own baseline, comparing their pre-Ramadan sample to their end-of-Ramadan sample.
What were the most important findings?
Fasting significantly increased microbial richness. Observed OTU counts rose after Ramadan (p = 0.016), while Shannon index and phylogenetic diversity showed no significant change. Across all samples, 27,521 operational taxonomic units were identified at 97 percent similarity. Community structure differed significantly before versus after fasting by unweighted UniFrac analysis (p = 0.025). LEfSe analysis found specific genera significantly enriched after fasting, and random forest analysis flagged a single bacterial species as the most affected by the fasting period.
What are the greatest implications of this study?
The results indicate that Ramadan fasting, an intermittent fasting regime, can reshape the gut microbiota within about a month. Richer and structurally distinct communities emerged after the fasting period. This supports the broader idea that meal timing, not only meal content, influences gut microbes. The authors caution that the sample was very small. Larger studies are needed to confirm which taxa change and whether these shifts carry health relevance.