A study of school-aged children (6–15 years old) in Northern Thailand reveals that obesity significantly alters both gut microbiota and fecal metabolites. Children with obesity exhibit an enrichment of specific bacteria, such as Faecalibacterium and Collinsella, while beneficial short-chain fatty acid (SCFA) producers are noticeably reduced.

Crucially, BMI influences fecal metabolite profiles more strongly than it does the overall microbiota composition. This relationship is not direct but is instead mediated through a “microbe–function–metabolite triangle”, where microbial biological functions act as a bridge. As BMI increases, dominant bacterial groups lose their functional connectivity, leading to a structural reorganization that favors obesity-associated taxa. Understanding this complex interplay is vital for developing precise strategies to prevent and manage pediatric obesity in Thai children.

Topic: Gut microbiome and fecal metabolite profiles in obese school-aged children from Northern Thailand

Authors: Therdtatha, P.| Granick, L. | Nachalam, P. | Jinatham, V.| Saninjuk, K. | Nakayama, J.| Popluechai, S.

Abstract: 

Although the gut microbiota of school-aged children has been extensively studied, there is a significant lack of knowledge regarding the relationship between fecal metabolite profiles and the gut microbiota in the context of obesity in young children, particularly in Thailand. To elucidate this association, we analyzed fecal gut microbiota and metabolites of 67 school-aged children across various body mass index (BMI) and categorized: normal (n = 30), overweight (n = 20), and obese (n = 17), employing next-generation sequencing (NGS) and ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS), respectively. Obese children exhibited distinct profiles of both gut microbiota and metabolites compared to N and OW children. Genera enriched in the OB group included Faecalibacterium, Collinsella, Megamonas, Brevundimonas, and Phascolarctobacterium. Nearly 80 percent of distinct negative-ion features were more abundant in the higher BMI groups. Multivariate analyses revealed that BMI had a stronger influence on variations in fecal metabolite profiles than on gut microbiota composition. Shifts in association patterns between the gut microbiota and predicted microbial functions (KOs) were observed across BMI groups. Although no direct associations were observed between gut microbiota and metabolites, microbiome–metabolite interactions were predominantly mediated through microbial functions. Our findings highlight non-targeted metabolites associated with high BMI in school-aged children and illustrate microbiome–metabolite crosstalk through a microbe–function–metabolite triangle, which may be mediated through functional pathways rather than direct taxon–metabolite correlations.

Source: Frontiers in Microbiology Volume 16 (September 2025)

Keywords: gut microbiota; gut metabolites; BMI; obesity; school-aged children

View at publisher: 

https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2025.1657839/full