Altered composition

What has emerged is that in individuals with raised fasting blood glucose levels or reduced glucose tolerance, a condition known as prediabetes, as well as in people with untreated type 2 diabetes, the gut microbiota is changed. Accordingly, the findings show that the gut microbiota can be used to identify individuals with diabetes.

The study also shows that, in the gut microbiota of study participants with prediabetes or who had developed type 2 diabetes, the potential to produce butyrate (a fatty acid that promotes hormone production in the gastrointestinal tract and controls inflammation) was reduced. This substance is formed mainly by beneficial bacteria in intestines as they digest dietary fibers. One possible implication is that altering individuals fiber intake and perhaps matching fiber types to specific microbiota, or development of next generation probiotics to add missing bacteria, may enable the development of novel diabetes prevention or therapeutics.

“Our study shows clearly that the composition of the gut microbiota may have a great potential for helping us to understand the risks of developing type 2 diabetes, and therefore improve our chances of detecting, preventing and treating the disease,” Bäckhed says.

Prevention at individual level
The results confirm the picture that the gut microbiota interacts with the body’s functions and internal conditions. The intestinal tract contains more than a kilogram of bacteria that are important for our health, and the kinds of gut bacteria found in people with type 2 diabetes seem to differ from those in healthy people.

“We hope to find patterns and identify which components of the gut microbiota identify individuals whose risk of developing type 2 diabetes is elevated. In the future, perhaps we’ll be able to prescribe individualized dietary changes, or develop new types of probiotic that can prevent or perhaps even treat the disease,” Bäckhed says.

The research now published builds on a population-based study that has been underway at the University of Gothenburg and Sahlgrenska University Hospital since 2013. It covered some 5,000 randomly selected people who were invited to take part in the study, and its purpose was to investigate which factors may entail an increased risk of type 2 diabetes. To confirm and verify the findings, the researchers also analyzed samples collected from the Swedish Cardiopulmonary Bioimage Study (SCAPIS), a nation-wide population study.