The effects of Jerusalem artichoke and fermented soybean powder mixture supplementation on blood glucose and oxidative stress in subjects with prediabetes or newly diagnosed type 2 diabetes

Background/Objectives: The objective of this study was to evaluate the effect of supplementation with a Jerusalem artichoke and fermented soybean powder mixture on blood glucose and oxidative stress levels. Subjects/Methods: This randomized, double-blinded, placebo-controlled study was conducted on 60 subjects with impaired fasting glucose (IFG), impaired glucose tolerance (IGT), or newly diagnosed type 2 diabetes. The subjects were randomly assigned to either a group that ingested 40 g of a Jerusalem artichoke and fermented soybean powder mixture (19.45 g each) daily or a group that received a placebo for 12 weeks. Paired t-test and independent t-test were performed for comparisons within groups and between groups, respectively. Results: Supplementation with the Jerusalem artichoke and fermented soybean powder mixture reduced the levels of fasting glucose (p < 0.001) and FFAs (p = 0.034), glucose at 60 min (p = 0.004), glucose (p = 0.006) areas under the response curve (AUC), homeostasis model assessment-insulin resistance (p = 0.018), and the urinary 8-epi- prostaglandin F-2 alpha (8-epi-PGF(2 alpha)) level (p = 0.028). The changes (Delta) in urinary 8-epi-PGF(2 alpha), glucose at 60 min, 120 min, and AUC, FFAs at 0 min and AUC were significantly different between the two groups. In addition, Delta glucose at 120 min (r = 0.472, p = 0.027) and the Delta glucose AUC (r= 0.572, p = 0.005) were positively correlated with Delta plasma malondialdehyde in the test group. Conclusions: The consumption of a Jerusalem artichoke and fermented soybean powder mixture for 12 weeks was effective for reducing postprandial glucose and oxidative stress level, particularly 8-epi-PGF(2 alpha), in subjects with IFG, IGT, or newly diagnosed type 2 diabetes.