Gut Microbiome Linked With Incident Type 2 Diabetes

Mitchel L. Zoler, PhD, for Medscape

November 29, 2021

Key Takeaways

  • Four species from the Lachnospiraceae family of bacteria that are common in the gut microbiome among healthy Finnish adults were associated with incident type 2 diabetes during long-term follow-up.

  • Researchers found the association in two geographically and genetically separate regions of Finland.

  • This unprecedented finding requires validation in different cohorts.

Why This Matters

  • The study results suggest that the makeup of the gut microbiome affects links between dietary habits, metabolic diseases, and type 2 diabetes.

  • The authors were unaware of any similar previous long-term, prospective studies of the association between type 2 diabetes and the gut microbiome.

  • The findings represent a step towards improved prediction of risk for incident type 2 diabetes and development of effective treatments through modification of the gut microbiome.

Study Design

  • Analysis of 5572 residents of Finland enrolled in the FINRISK study in 2002 when they were 24-74 years old.   

  • All participants had a stool specimen collected at enrollment that was subsequently analyzed for its microbiome content.

  • Researchers tracked incident type 2 diabetes during a median follow-up of 15.8 years.

Key Results

  • During follow-up, 432 people (8%) developed incident type 2 diabetes.

  • Out of 119 different taxa identified in the specimens, 15 had positive associations with incident type 2 diabetes and three had negative associations in analyses that adjusted for several known risk factors.

  • Most of the positively associated taxa were from the family Lachnospiraceae, with several from the genus Clostridium. Two of the three negatively associated taxa were from the genus Alistipes.

  • Overall, the investigators identified four species from the family Lachnospiraceae that showed robust association with a higher type 2 diabetes risk in two geographically and genetically separate regions of Finland.

  • All four of the diabetes-associated taxa have been previously linked with other metabolic diseases and risk factors, such as obesity and fatty liver disease.


  • The study used a technique known as shallow shotgun metagenomics to analyze the microbiome contents, which limits the study to describing associations between taxa and incident disease.

  • This depth of genetic sequencing precludes more comprehensive and detailed genomic assessments. 


  • The study was primarily supported by grants from several noncommercial organizations in Finland. A collaborating US microbiome research center received funding from Illumina and Janssen.

  • One author has received honoraria from Servier, and another has received honorarium from Sanofi and research support from Bayer.

This is a summary of a preprint research study written by a research team led by several investigators based in Finland available on MedRxiv provided to you by Medscape. This study has not yet been peer reviewed. The full text of the study can be found on


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