Researchers at Chalmers University of Technology led a large Swedish study of 4,685 adults and discovered that changes in gut microbiota and metabolism can show up years before type 2 diabetes develops. Participants gave stool samples, and 383 developed diabetes after ∼5 years of follow-up.
Key bacterial links:
- 9 specific bacteria were associated with future diabetes risk.
- Akkermansia muciniphila – usually seen as beneficial – was high in people who later developed diabetes. Researchers think that with low fiber intake, it eats the gut’s protective mucus instead of fiber, causing inflammation and insulin resistance.
- Coprococcus catus – very low levels were linked to diabetes risk, but above a certain level the risk disappeared.
- Diet mattered: whether certain gut bacteria were helpful or harmful depended on a person’s eating habits.
Why it matters: The findings suggest gut microbiome changes come before diabetes, not as a result of it. This means stool samples could eventually be used as biomarkers, alongside obesity, genetics, and blood glucose, to identify people at risk earlier and start preventive measures.
Next steps: Results still need validation in larger studies. If confirmed, the microbiome could become a target for personalized prevention through diet and lifestyle, since it can be modified. The study supports current advice to eat fiber-rich foods like fruit, vegetables, legumes, and whole grains.