Yacon ( <i>Smallanthus sonchifoliu</i> s) Root Increases Bowel Movement Frequency in Healthy Adults via Modulating Gut Microbiota and Intestinal Metabolites: A Pilot Study

Yacon root (YR) is a functional food that can increase bowel movement frequency, but with an unclear mechanism. In this study, a UPLC-Orbitrap-MS/MS system was employed to characterize the chemical composition of YR. Subsequently, a 10-day pilot intervention trial involving 11 healthy adults was conducted to evaluate the effects of YR on bowel movement frequency. Concurrently, the involved mechanisms were explored through metagenomic and metabolomic approaches. A total of 82 chemical components were identified in YR. Clinical trials indicated that continuous intake of YR significantly increased bowel movement frequency without noticeable adverse effects. Metagenomic analysis revealed that YR substantially increased the abundance of beneficial bacteria such as Bifidobacterium and inhibited the generation of potential pathogens, including Escherichia-Shigella, thereby promoting a more balanced and healthier gut microbiota structure. Metabolomic analysis indicated that YR significantly upregulated metabolites, including cholic acid, taurine, and amino acids, which mainly focus on the biosynthesis of primary bile acid and the metabolism of taurine and hypotaurine. In summary, YR can safely and effectively increase bowel movement frequency in healthy individuals. The mechanism may involve synergistic regulation of gut microbiota and metabolites, which offered new insights to support YR as a natural functional food for laxative effects.