Oral and fecal microbiota in Chinese adults with obesity reveal potential niche-specific microbiota associated with obesity

Sep 30, 2026

Obesity represents a major preventable health threat, and growing evidence links imbalances in gut and oral microbiota to weight gain and metabolic dysfunction. This study analyzed both oral and fecal microbiota in adults with obesity to uncover niche-specific microbial signatures. Comparisons with non-obese controls showed distinct differences in community composition and diversity, and obesity-related co-occurrence patterns were niche-specific, with stool networks showing reduced modularity. Machine learning and statistical analyses identified saliva-associated taxa associated with obesity.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages14

Reading Time35 min

AccessFree to download

Abstract

Background

Results

Conclusions

Keywords

Hu etal. BMC Microbiology (2026) 26:17 [https://doi.org/10.1186/s12866-025-04561-9](https://doi.org/10.1186/s12866-025-04561-9) BMC Microbiology RESEARCH Open Access Oral and fecal microbiota in Chinese adults with obesity reveal potential niche-specific microbiota associated with obesity Junqing Hu 1,2,3*, Pengsen Guo2,4, Jiahui Yu2,4, Ting Zhang 1,2 and Xixi Yang 1,2,3* Abstract Background Obesity has emerged as a global health crisis. Increasing evidence suggests that imbalances in gut and oral microbiota are linked to obesity, with specific microbial profiles influencing metabolic dysfunction and weight gain. Given the distinct ecological niches and the importance of gut and oral microbiota in obesity, this study analyzed both oral and fecal microbiota in adults with obesity, aiming to identify potential niche-specific microbial signatures associated with the condition. Results The comparison of fecal and oral microbiota communities between individuals with obesity and non-obese controls revealed significant differences in microbial composition and diversity. The predominant genera identified in both sample types were Prevotella, Faecalibacterium, Streptococcus, and Porphyromonas. A notable restructuring of microbial communities was observed between fecal and oral samples, regardless of obesity status. Furthermore, obesity-associated changes in microbial co-occurrence networks were found to be niche-specific, with reduced modularity in stool samples. In contrast, saliva microbial networks appeared to be more compartmentalized than those in stool. MaAsLin 3 and ANCOM-BC2 analyses identified five niche-specific taxa associated with obesity. These included positive associations in saliva with Granulicatella sp902479935, Lancefieldella sp938036925, Peptostreptococcus stomatis, Rothia sp916715725, as well as a negative association in saliva with Faecalibacterium sp934503275 . Mediation analysis indicated that the second principal component partially mediated these effects, with Lancefieldella sp938036925 and others serving as positive contributors. The taxa Wolinella, Phocaeicola, and Bulleidia, which exhibited high abundance in saliva, were consistently selected by all machine learning models. Conclusions This study contributes to the growing body of literature investigating the relationship between obesity and microbial communities. Using 16 S rRNA gene ampl icon sequencing, we characterized distinct microbial compositions in both saliva and fecal samples from individuals with obesity compared to normal-weight controls within a defined geographic population. The results suggest that the salivary microbiome may contain potential associative biomarkers indicative of obesity risk, warranting further in-depth investigation. Keywords Obesity, Oral microbiota, Fecal microbiota, Bacteria, Biomarkers *Correspondence: Junqing Hu [hujunqing@swjtu.edu.cn](hujunqing@swjtu.edu.cn)[ ](hujunqing@swjtu.edu.cn)Xixi Yang [yangxixi@swjtu.edu.cn](yangxixi@swjtu.edu.cn) Full list of author information is available at the end of the article © The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need t

FAQs

What was the main goal of the study?

To analyze both oral and fecal microbiota in Chinese adults with obesity and identify potential niche-specific microbial signatures associated with obesity.

What did the study find when comparing obese and non-obese participants?

Fecal and oral microbiota communities differed significantly in microbial composition and diversity between obese individuals and non-obese controls.

Which analyses were used to identify obesity-associated niche-specific taxa?

MaAsLin 3 and ANCOM-BC2 analyses identified five niche-specific taxa associated with obesity, with additional mediation analysis supporting partial effects.

Sep 30, 2026

Uploaded by Guten tag