Objective: Upon food digestion, the gut microbiota plays a pivotal role in energy metabolism, affecting the development of type 2 diabetes (DM) . We aimed to examine the influence of nutrients consumed on the association between the gut microbiota and DM.
Research Design and Methods: Among participants of the population-based Iwaki study of Japanese held in 2016, those with information of gut microbiota (n=1148) were included. The following individuals were also excluded: over 77 years of age (excluded to minimize age-related diversity in gut microbiota as previously reported) , and were the 55 individuals with an incomplete data set. After these exclusions, 10individuals (403 men, 616 women) aged 52.4 ± 14.1 years were included in the present study.
Results: Compared with non diabetic subjects, diabetic subjects had larger proportions of the genera Bifidobacterium and Streptococcus but smaller proportions of the genera Roseburia and Blautia in their gut microbiotas. The genera Streptococcus and Roseburia were positively correlated with the amounts of energy (β= 0.064, p=0.0297) and of carbohydrate and fiber (β= 0.079, p=0.0069, and β=0.069, p=0.0129, respectively) consumed, respectively. In contrast, the genera Bifidobacterium and Blautia were not correlated with any nutrients consumed. Cluster analyses of these four genera revealed that the Blautia-dominant cluster was most protective against DM, whereas the Bifidobacterium-dominant cluster was a risk for DM, after adjustment for multiple factors including nutrients consumed (vs. the Blautia-dominant cluster; odd ratio 3.97, 95% confidence interval 1.68-9.36) .
Conclusions: Positive correlations of the genera Streptococcus and Roseburia indicate the possible involvement of nutrient factors in the association between the gut microbiota and DM. Furthermore, having a Bifidobacterium-dominant gut microbiota may be a risk for DM whereas having a Blautia-dominant gut microbiota may be protective against DM.
A.Tamura: None. M.Daimon: None. A.Kamba: None. S.Mizushiri: None. M.Murabayashi: None. Y.Nishiya: None. R.Ito: None. S.Ono: None.