Food, Global Health Reading time 3 min
Parkinson’s disease: discovery of a specific signature in the gut microbiome
PRESS RELEASE - An international team led by University College London (United Kingdom), with the involvement of INRAE in France, has discovered and characterized changes in the gut microbiome that are specific to Parkinson’s disease. The researchers developed an innovative analytical method to study the gut microbiome of individuals from a cohort of 464 people in Italy and the UK, including 271 patients with Parkinson’s disease. By comparing their results with gut microbiome data from three other cohorts of Parkinson’s patients in the United States, South Korea and Türkiye, they confirmed that all patients exhibited the same microbiome changes to varying degrees depending on the stage of disease progression. These findings, published in Nature Medicine, pave the way for the development of tests to identify people at risk of developing Parkinson’s and to recommend preventive measures, particularly through diet, to slow disease onset.
Published on 20 April 2026
Neurodegenerative diseases, such as Parkinson’s, are on the rise: according to the WHO, their prevalence has doubled in 25 years. While ageing is the main risk factor, some people may have a genetic predisposition: a quarter of Parkinson’s patients carry mutations in a gene called GBA. However, only 10% of people carrying these mutations go on to develop the disease. Diagnostic tests for Parkinson’s are time-consuming and costly, and it is not yet possible to identify individuals at risk of developing the disease with a view to slowing down and perhaps preventing its progression.
The research team monitored and analysed the gut microbiomes of individuals from a cohort of 464 people in the United Kingdom and Italy to characterize the changes and their link to the development of Parkinson’s disease. The cohort included 271 patients with Parkinson’s disease, 43 individuals with a genetic predisposition but who had not developed the disease, and 150 people without a genetic predisposition. In addition to the microbiome analysis, the individuals in the cohort were examined to assess their clinical status in relation to the Parkinson’s diagnosis.
An innovative analytical method and microbiome changes specific to Parkinson’s disease
The researchers developed a new method for analysing the gut microbiome using faecal samples from cohort participants. Each person’s gut microbiome is composed of several hundred different species of microorganisms. Conventional microbiome analyses focus on individual species, the abundance of which varies between individuals. Within the gut microbiome, microorganisms of different species work together and change their abundance in a coordinated manner in response to disease or diet. For this study, the researchers focused on these coordinated changes to detect abnormalities in the overall composition of the microbiome.
Using this new method, the researchers identified a specific signature of Parkinson’s disease in the gut microbiome, with certain groups of species becoming depleted and others enriched to varying degrees, depending on the stage of the disease. Patients in the most advanced stages of the disease exhibited changes in their microbiome that were 15 times more severe than those in patients in the early stages. Additionally, analysis of gut microbiome data from participants in three other patient cohorts in the United States, Türkiye and South Korea revealed the same microbiome changes, regardless of the patients’ origins.
In the group of individuals with a genetic predisposition but who had not developed the disease, similar changes in the microbiome were observed, but to a lesser extent than in patients with the disease. The 10% of individuals with the most pronounced changes were the most likely to develop Parkinson’s based on the clinical examinations. Similarly, among the group of people without a genetic predisposition, 20% of those with the most pronounced changes in the microbiome exhibited clinical signs more closely resembling those of patients with Parkinson’s, suggesting an increased risk of developing the disease.
Finally, regardless of drug treatment, the least pronounced changes in the microbiome and the least severe symptoms were observed in patients following a balanced diet, suggesting that diet could moderate disease onset and progression. Previous studies have shown that a diet similar to the Mediterranean diet1 may delay the onset of Parkinson’s (Metcalfe-Roch A. et al. (2021) Movement Disorders, vol. 36, DOI : 10.1002/mds.28464).
This study demonstrates progressive changes in the gut microbiome that are specific to Parkinson’s disease. These findings pave the way for the development of tests to identify individuals most at risk of developing the disease through analysis of their gut microbiome.
“By analysing the gut microbiome, we can identify individuals at risk of developing Parkinson’s disease and offer them support and ways to reduce this risk, such as through diet.”
Stanislav Dusko Ehrlich, Honorary Senior Research Fellow at University College London
“This innovative microbiome analysis method, which tracks the entire microbial community rather than individual species, has made it possible to identify changes specific to Parkinson’s disease.”
Mathieu Almeida, Research Scientist at INRAE in MetaGenoPolis unit
Reference
Menozzi E. et al. (2026). Microbiome signature of Parkinson’s disease in healthy and genetically at-risk individuals. Nature Medicine DOI : https://doi.org/10.1038/s41591-026-04318-5
[1] The Mediterranean diet is known as a healthy, balanced way to eat, with weekly meals emphasizing home cooking and a diverse range of foods, including lots of fruit and vegetables, nuts, and whole grains; moderate amounts of vegetable oils and fatty fish; and very little meat or fatty, sugary and salty foods. (learn more on Eufic.fr)