European journal of nutrition. 2023;62(5):2015-2026
Plain language summary
Primary bile acids (priBAs) are synthesised from cholesterol in the human liver, conjugated with either taurine or glycine [amino acids], and secreted into the intestinal tract, where they dissolve dietary lipids. Diet is a modifiable factor that can influence defecation status, BAs, and intestinal microbiota. The aim of this study was to identify associations among defecation status, intestinal microbiota, and diet by examining faecal BA composition in community-dwelling young participants. This study was a cross-sectional study which enrolled 70 students. Results showed that 20.9% of the participants had high faecal BA levels with predominantly priBAs. This cluster was associated with an increased relative abundance of Clostridium subcluster XIVa [bacteria], increased frequency of normal faeces, and decreased relative abundance of Bacteroides and Clostridium cluster IV [bacteria]. Conversely, high levels of cytotoxic [toxic to cells] secondary BA (secBA) were associated with low normal defecation frequency, low insoluble fibre intake, and high animal fat intake. Authors concluded that among community-dwelling young adults, secBA production is affected by both dietary and lifestyle related factors. Thus, their findings may inform novel strategies for preventing colorectal cancer and cholelithiasis.