Fecal microbiota transplantation in obesity: a comprehensive overview from basic research to clinical application

Background Obesity involves microbiota dysbiosis, low-grade inflammation, and insulin resistance, which interacts with multiple metabolic disorders. Fecal microbiota transplantation (FMT) is an emerging therapeutic approach in obesity that enhances intestinal barrier function and regulates energy metabolism. Aim To provide a comprehensive overview of publication trends, research collaborations, hotspots, future directions, and the current clinical application status of FMT in obesity. Methods Literature searches were conducted in the Web of Science (WoS) and PubMed databases. The primary analysis was performed using the WoS database for bibliometric analysis, while PubMed was searched to supplement the clinical research landscape, ensuring data comprehensiveness and methodological rigor. Results A total of 517 papers were finally included, of which 116 (22.44%) were published in the top 10 academic journals. Most publications originated from China ( n = 246, 47.6%) and Zhejiang University contributed the most publications ( n = 18, 3.5%). Gut Microbes ranked first (21 publications, IF 10.931), followed by Frontiers in Microbiology (19, IF 4.504) and Nutrients (14, IF 4.919). Research hotspots have shifted toward “targeting the gut microbiota.” “Oral supplementation” and targeted “prebiotics” may be more accessible in the future. The mini literature review of 21 clinical trials revealed that metabolic improvements following FMT are often transient and highly variable across individuals. No standardized protocol for donor selection, delivery route, or outcome measurement currently exists, and most trials had small sample sizes. Conclusion Although FMT shows promise, its clinical benefits remain transient and variable across individuals. Current evidence does not yet support routine clinical application. Targeted oral microbiota supplementation may represent a future direction, but high-quality, large-scale clinical trials are urgently needed to establish standardized protocols and evaluate long-term safety and efficacy.