Effects of daily consumption of synbiotic bread on insulin metabolism and serum high-sensitivity C-reactive protein among diabetic patients: a double-blind, randomized, controlled clinical trial.

BACKGROUND: This study was conducted to evaluate the effects of daily consumption of synbiotic bread on the metabolic status of patients with type 2 diabetes mellitus.

METHODS: This randomized, double-blind, controlled clinical trial was performed in 81 diabetic patients. The subjects were randomly assigned to consumption of synbiotic (n = 27), probiotic (n = 27), or control bread (n = 27) for 8 weeks 3 times a day in a 40-gram package. The synbiotic bread contained Lactobacillus sporogenes (1 × 10(8) CFU) and 0.07 g inulin per 1 g. The probiotic bread contained L. sporogenes (1 × 10(8) CFU per 1 g). Fasting blood samples were taken at baseline and after an 8-week intervention for quantification of related factors.

RESULTS: Consumption of the synbiotic bread resulted in a significant reduction in serum insulin levels (-3.2 ± 5.4 vs. -0.3 ± 3.4 and 0.6 ± 4.7 µIU/ml, respectively, p = 0.007), homeostatic model assessment for insulin resistance scores (-1.5 ± 2.7 vs. -0.2 ± 1.6 and 0.4 ± 3.5, respectively, p = 0.03), and homeostatic model assessment-β-cell function (-7.2 ± 16.3 vs. -0.7 ± 10.8 and 0.7 ± 8.2, respectively, p = 0.04) compared to the probiotic and control breads. We did not find any significant effect of synbiotic bread consumption on fasting plasma glucose, the quantitative insulin sensitivity check index, or serum hs-CRP levels compared to other breads.

CONCLUSION: Consumption of the synbiotic bread among diabetic patients had beneficial effects on insulin metabolism.