Anthocyanins increase serum adiponectin in newly diagnosed diabetes but not in prediabetes: a randomized controlled trial

Abstract Background Epidemiological studies have suggested that adiponectin is associated with the development of insulin resistance and type 2 diabetes. This study first examined the effect of purified anthocyanins, a group of dietary flavonoids, on serum adiponectin in patients with prediabetes and newly diagnosed diabetes.Methods A total of 160 patients with prediabetes (n=90) or newly diagnosed diabetes (n=70) were randomly assigned to either the anthocyanins group or the placebo group for 12 weeks of intervention. Serum adiponectin, a set of biomarkers related to glucolipid metabolism, anthropometric parameters, dietary intake and physical activity were measured before and after intervention.Results Anthocyanins increased serum adiponectin compared with placebo (net change 0.46 µg/mL, 95% CI [0.03, 0.90], p=0.038) in the subjects with newly diagnosed diabetes. No significant difference in the change in adiponectin was observed between the two groups either in the overall subjects (0.02 µg/mL [-0.32, 0.36], p=0.906) or in prediabetes (-0.35 µg/mL [-0.85, 0.16], p=0.174). Anthocyanins also decreased fasting glucose (-0.5 mmol/L [-1, -0.04], p=0.035) in the subjects with newly diagnosed diabetes, but no such change was observed in those with prediabetes.Conclusions Anthocyanins supplementation for 12 weeks improved serum adiponectin and fasting glucose in patients with newly diagnosed diabetes, but not in patients with prediabetes.