THE ROLE OF FAECAL MICROBIOTA TRANSPLANTATION (FMT) IN THE TREATMENT OF OBESITY — A SYSTEMATIC REVIEW INCLUDING THE LATEST RESEARCH FROM 2020–2025
Abstract
FMT is a very promising, though still experimental, method of influencing the composition and functioning of the gut microbiota. In recent years, more and more research teams have been focusing on its potential in the treatment of obesity, type 2 diabetes, metabolic syndrome and lipid metabolism disorders. Publications show that FMT can lead to permanent changes in the recipient's microbiome, including increased species diversity, an increase in the number of bacteria producing short-chain fatty acids, and modification of metabolic pathways related to glucose and lipid metabolism. The relationships between the gut microbiota and the functioning of the immune and nervous systems are also becoming better understood, opening up new therapeutic possibilities. The collection and critical analysis of clinical and experimental research results not only allows us to determine the safety and tolerance of this method, but also to indicate the directions in which future projects should be developed in order to fully assess its effectiveness in the long term.
The aim of the study was to collect and organise the results of clinical trials on the use of faecal microbiota transplantation (FMT) in people with obesity or metabolic syndrome, to assess the impact of this method on metabolic parameters, and to analyse the current state of knowledge on the impact of FMT on weight loss, metabolic parameters and gut microbiome composition in individuals with obesity, in light of studies from 2020–2025, and to identify the mechanisms of action of faecal microbiota transplantation (FMT) and determine its therapeutic potential in the treatment of obesity based on the results of the above-mentioned studies.
Ten randomised controlled trials comparing FMT with placebo or standard treatment were included in the analysis. It was found that faecal microbiota transplantation may have a beneficial effect on metabolic parameters such as insulin sensitivity and lipid profile, but its efficacy and durability require confirmation in longer, better-designed clinical trials.
References
Allegretti, J. R., Kassam, Z., Mullish, B. H., Chiang, A., Carrellas, M., Hurtado, J., Marchesi, J. R., McDonald, J. A. K., Pechlivanis, A., Barker, G. F., Miguéns Blanco, J., Garcia-Perez, I., Wong, W. F., Gerardin, Y., Silverstein, M., Kennedy, K., & Thompson, C. (2020). Effects of Fecal Microbiota Transplantation With Oral Capsules in Obese Patients. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association, 18(4), 855–863.e2.https://doi.org/10.1016/j.cgh.2019.07.006
Da Ponte Neto AM, Clemente ACO, Rosa PW, Ribeiro IB, Funari MP, Nunes GC, Moreira L, Sparvoli LG, Cortez R, Taddei CR, Mancini MC, de Moura EGH. Fecal microbiota transplantation in patients with metabolic syndrome and obesity: A randomised controlled trial. World J Clin Cases. 6 July 2023;11(19):4612-4624. doi: 10.12998/wjcc.v11.i19.4612. PMID: 37469721; PMCID: PMC10353513.
Hanssen, H. M., Fjellstad, M. S., Skjevling, L., Johnsen, P. H., Kulseng, B., Goll, R., Almå, K. H., & Valle, P.-C. (2023). A randomised, placebo-controlled, double-blind study of faecal microbiota transplantation in severely obese individuals: study protocol. BMJ Open Gastroenterology and Hepatology, 13, e073242. https://doi.org/10.1136/bmjopen-2023-073242
Lahtinen, P., Juuti, A., Luostarinen, M., Niskanen, L., Liukkonen, T., Tillonen, J., Kössi, J., Ilvesmäki, V., Viljakka, M., Satokari, R., & Arkkila, P. (2022). Effectiveness of Fecal Microbiota Transplantation for Weight Loss in Patients With Obesity Undergoing Bariatric Surgery: A Randomised Clinical Trial. JAMA Network Open, 5(12), e2247226. https://doi.org/10.1001/jamanetworkopen.2022.47226
Leong, K. S. W., Jayasinghe, T. N., Wilson, B. C., et al. (2020). Effects of faecal microbiome transfer in adolescents with obesity: The Gut Bugs randomised controlled trial. JAMA Network Open, 3(12), e2030415. https://doi.org/10.1001/jamanetworkopen.2020.30415
Mocanu, V., Zhang, Z., Deehan, E. C., Kao, D. H., Hotte, N., Karmali, S., Birch, D. W., Samarasinghe, K. K., Walter, J., & Madsen, K. L. (2021). Fecal microbial transplantation and fibre supplementation in patients with severe obesity and metabolic syndrome: a randomised double-blind, placebo-controlled phase 2 trial. Nature medicine, 27(7), 1272–1279. https://doi.org/10.1038/s41591-021-01399-2
Ng, S. C., et al. (2021). Microbiota engraftment after faecal microbiota transplantation in obese subjects with type 2 diabetes: a 24-week, double-blind, randomised controlled trial. Gut. https://doi.org/10.1136/gutjnl-2020-323617
Yu EW, Gao L, Stastka P, Cheney MC, Mahabamunuge J, Torres Soto M, Ford CB, Bryant JA, Henn MR, Hohmann EL. Fecal microbiota transplantation for the improvement of metabolism in obesity: The FMT-TRIM double-blind placebo-controlled pilot trial. PLoS Med. 9 March 2020;17(3): e1003051. doi: 10.1371/journal.pmed.1003051. PMID: 32150549; PMCID: PMC7062239.
Zhou, X., Zhang, C., & Li, Y. (2023). Effect of faecal microbiota transplantation on metabolic syndrome: a meta-analysis of randomised controlled trials. PLOS ONE, 18(7), e0288718. https://doi.org/10.1371/journal.pone.0288718
Zuppi, M., Vatanen, T., Wilson, B.C., et al. Faecal microbiota transplantation alters gut phage communities in a clinical trial for obesity. Microbiome 12, 122 (2024). https://doi.org/10.1186/s40168-024-01833-w
Stupnicki, R., & Tomaszewski, P. (2000). Body mass index and body fat content in adults. Antropomotoryka, 21, 335–343.
WHO: Obesity and overweight – Key facts: "Worldwide adult obesity has more than doubled since 1990, WHO, https://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight , accessed on 03.10.2025
Collaboration on Risk Factors for Noncommunicable Diseases (NCD-RisC). Global trends in body mass index, underweight, overweight and obesity from 1975 to 2016: a meta-analysis of 2,416 population-based studies involving 128.9 million children, adolescents and adults. Lancet. 2017;390(10113):2627–2642. doi:10.1016/S0140-6736(17)32129-3
Juszczuk K., Grudlewska K., Mikucka A.: Gut microbiota transplantation – a method of treating recurrent Clostridium difficile infections and other diseases. Postępy Hig. Med. Dośw, 2017;71:220–226 ; Stolarz W., Piotrowski D., Blaszkowska M.: Clinical significance of Clostridium difficile carriage in patients undergoing antibiotic therapy. PRZEGL EPIDEMIOL, 2020;74(1): 3-10.
Copyright (c) 2025 Hanna Pietruszewska, Oliwia Sędziak, Natalia Kruszewska, Sabina Skrzynecka, Urszula Borucińska

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