Multi-omics analyses reveal relationships among polyphenol-rich oolong tea consumption, gut microbiota, and metabolic profile: A pilot study

[Display omitted] •3-week intake of oolong tea impacted gut microbial and metabolic profile of healthy adults.•Observed species and α-diversity of gut microbiota were increased by oolong tea consumption.•Oolong tea intake led to enriched Bacteroides and Prevotella, and decreased Megamonas.•Gut microbes from overweight subjects showed greater response to oolong tea treatment.•Rise in fecal consistency potentially related to enriched metabolites and metabolic pathways. Convincing evidence has suggested the health potentials of oolong tea (OT) on gut microbiota homeostasis; however, limited population-based studies exist regarding the effect of OT consumption on human gut microbial and metabolic profile. This pilot study explored gut microbial and metabolic changes in healthy adults with a 3-week oolong tea intake. Our findings showed that OT treatment significantly altered gut microbial diversity (Shannon index, 5.4±0.1 vs. 5.7±0.1 pre- and post-OT treatment), reorganized gut microbiota composition, enriched Bacteroides and Prevotella, decreased Megamonas, and improved gastrointestinal function. Also, gut microbes from overweight subjects with BMI >23.9 exhibited greater responses to OT treatment compared with normal-weight counterparts. Metabolomic analysis identified OT intake-induced 23 differential metabolites and 10 enriched metabolic pathways. This study may provide new insights into the association among OT intervention, host gut microbiome and metabolic profile, and improve the knowledge of clinical strategies and personalized nutrition.