New Kerala Study Highlights Potential Connection Between Gut Microbiome and Parkinson's Disease

Could the bacteria living in your gut provide clues about Parkinson's disease and its progression? A new Indian study has identified significant differences in the gut bacteria of people with Parkinson's disease compared with healthy individuals, suggesting a possible connection between gut health, brain function and disease severity.

Published in the journal npj Parkinson's Disease, the study was conducted by researchers from Cochin University of Science and Technology (CUSAT) and Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST), Thiruvananthapuram, Kerala.

Parkinson's disease is a progressive neurological disorder in which dopamine-producing nerve cells gradually deteriorate, leading to symptoms such as tremors, muscle stiffness and slowed movements.

Researchers examined 130 participants, including 65 patients with Parkinson's disease and 65 healthy individuals, most of whom were spouses of the patients.

The researchers analysed stool samples using 16S rRNA gene sequencing to identify differences in gut bacterial composition and examine their potential biological functions.

The findings revealed that patients with Parkinson's disease had higher levels of certain bacteria associated with inflammation and lower levels of beneficial bacteria involved in producing short-chain fatty acids.

These fatty acids help maintain the intestinal barrier and regulate immune responses.

Importantly, researchers found that differences in gut bacterial composition were associated with Parkinson's disease severity and other clinical characteristics.

The study also suggested possible links between gut bacteria and biological pathways involving dopamine, glutamate and GABA, chemicals essential for brain signalling.

Researchers proposed that altered gut bacteria could contribute to intestinal barrier dysfunction and inflammation, potentially influencing neurological processes.

However, the study could not establish whether changes in gut bacteria cause Parkinson's disease or occur as a consequence of the condition. Larger studies are needed to confirm these associations and determine their clinical significance.

REFERENCE: Painadath Alikunju, A., Jose, D., Venkatachalam, S. et al. Integrative microbiome and functional profiling decodes pro-inflammatory gut microbiome signatures in South Indian patients with Parkinson’s disease. npj Parkinsons Dis. (2026). https://doi.org/10.1038/s41531-026-01547-w