Metabolic problems represent one of the major health concerns which are attractive for being addressed by nutritional interventions, as these are directly connected to dietary habits.Anthocyans possess cardiovascular disease prevention, obesity control, and diabetes alleviation properties, but association between anthocyans and prediabetes need to be more firmly understood and established from robust clinical data. However, there is little human research that has reported on the efficacy of increased anthocyans bioactive consumption on insulin sensitivity in pre-diabetes.

The investigators plan to conduct a randomized double-blind, placebo-controlled trial to characterize the potential effects of anthocyans, purified from bilberries and blackcurrants, on metabolic abnormalities commonly associated with type 2 pre-diabetes.

Inclusion Criteria:

• FPG 100 mg/dL (5.6 mmol/L) to 125 mg/dL (6.9 mmol/L) (IFG) OR 2-h plasma glucose in the 75gOGTT 140 mg/dL (7.8 mmol/L) to 199 mg/dL (11.0 mmol/L)(IGT) OR HbA1C 5.7-6.4%.
• Newly diagnosed T2DM who exceed the upper limit of the range but has not yet accepted hypoglycemic therapy.

Exclusion Criteria:

Patients with cardiac, renal, or hepatic diseases or with hyperthyroidism or who had concomitant infections, or who use of anti-diabetic drug or potential affect plasma glucose drugs, pregnant and breast-feeding women, and with polycystic ovarian syndrome.