A dietary intervention for postmenopausal hot flashes: A potential role of gut microbiome. An exploratory analysisOriginal 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 exploratory analysis asked whether gut microbiome changes help explain how a plant-based diet reduces postmenopausal hot flashes. Postmenopausal women were randomized to a low-fat vegan diet with daily cooked soybeans or to their usual diet for 12 weeks. Hot flash frequency and severity were logged with a mobile app. In a subset, the gut microbiome was sequenced by deep shotgun metagenomics at baseline and 12 weeks, and bacterial changes were correlated with hot flash changes.
Who was studied?
The trial enrolled 84 postmenopausal women reporting at least two moderate-to-severe hot flashes daily. Participants were randomized in two successive cohorts to the dietary intervention or usual diet. The microbiome substudy analyzed a subset of 11 women in the intervention group. This was a human randomized controlled trial. Pearson correlations linked changes in hot flashes to changes in gut bacteria, with adjustment for body mass index in key analyses.
What were the most important findings?
In the microbiome subset, total hot flashes fell by 95 percent during the intervention, and severe hot flashes disappeared. Moderate-to-severe hot flashes dropped by 96 percent, with daytime down 96 percent and nighttime down 94 percent. Alpha and beta diversity did not change significantly. Several taxa shifted, but none survived correction for multiple comparisons. Changes in Porphyromonas and Prevotella corporis correlated with fewer severe daytime hot flashes, and Clostridium asparagiforme changes correlated with fewer severe nighttime hot flashes.
What are the greatest implications of this study?
The findings raise the possibility that gut bacteria partly mediate how a plant-based, soy-containing diet reduces menopausal hot flashes. Because the microbiome subset had only 11 women and taxonomic differences lost significance after correction, these are associations, not proof of cause. The strong symptom reduction is notable but comes from a small exploratory sample. The authors stress that larger randomized trials are needed before drawing firm conclusions about the microbiome's role.