Modulating the Human Gut Microbiome and Health Markers through Kombucha Consumption: A Controlled Clinical Study

Fermented foods are surging in popularity globally due to their links to metabolic health and the gut microbiome. However, direct clinical evidence for the health claims is lacking. Here, we describe an eight-week clinical trial that explored the effects of a kombucha supplement in healthy individuals consuming a Western diet, randomized into the kombucha ( n = 16) or control (n = 8) group. We collected longitudinal stool and blood samples to profile the human microbiome and inflammation markers. Paired analysis between baseline and end of intervention time points within kombucha or control groups revealed increases in fasting insulin and in HOMA-IR in the kombucha group whereas reductions in HDL cholesterol were associated with the control group. Shotgun metagenomic analysis revealed the relative abundance of Weizmannia, a kombucha-associated probiotic to be overrepresented in consumers at the end of the intervention. Short-term kombucha intervention induced modest impacts on human gut microbiome composition and biochemical parameters. HighlightsO_LIThere is a global rise in popularity of fermented foods due to their links to metabolic health. However, empirical evidence supporting the health conferring benefits is lacking. C_LIO_LIThis eight-week randomized controlled clinical trial tested the effect of kombucha on gut microbiome and inflammation in healthy participants consuming a Western diet. C_LIO_LIBiochemical indicators and inflammation markers were not different between the control and intervention groups at the end of the intervention. C_LIO_LIKombucha-associated probiotic, Weizmannia and short chain fatty acids synthesizing microbes were enriched in consumers after 4 weeks of kombucha intervention. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/24309793v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@11757d5org.highwire.dtl.DTLVardef@187638forg.highwire.dtl.DTLVardef@19961deorg.highwire.dtl.DTLVardef@e85fac_HPS_FORMAT_FIGEXP M_FIG C_FIG