The incidence rate of type 2 diabetes in Thai populations is high and increasing every year. Cardiovascular disease is the main complication of this disease, which has been defined as an important cause of death among Diabetic patients. This disease is now becoming a major health problem and causes a great economic loss to the country. Evidence shows that Curcumin, Thai herbal medicine, has the effectiveness of prevention and delay of type 2 diabetes. However, there is no scientific study that aims to prove the efficacy of this herb particularly for prevention and delay the disease in Patients with impaired glucose tolerance (pre-diabetes) and insulin resistance.

Inclusion Criteria:

• Patients aged 35 years or older with an abnormal fasting plasma glucose (100-125 mg/dl) or with insulin resistance (140-199 mg/dl) by using 75 mg of glucose OGTT.

Exclusion Criteria:

• Have been diagnosed with diabetes by the results of FPG >/=126 mg/dl
• Present with secondary peripheral arterial disease (PAD)
• Present with cardiovascular diseases such as coronary arterial disease and cerebrovascular disease
• Receive anticoagulant drugs that have an effect on the measurement of pulse wave velocity (PWV)
• Receive antihypertensive or lipid-lowering drugs (ARB, ACEI, fenofibrate, atorvastatin, rosuvastatin, fluvastatin) that have an effect on the measurement of C-reactive protein (CRP)
• Present with kidney failure (serum creatinine > 2.0 mg/dl) or in the process of renal dialysis
• Present with hepatitis (ALT level >/= 3 times the upper limit)
• Receive any herbal medications or curcumin
• Present with high blood sugar from other causes apart from type 2 diabetes such as receiving steroid drugs, cancer or pancreatic cyst
• Present with infection or inflammation that have effect on the level of CRP
• Pregnancy or breastfeeding
• Have a history of gall bladder diseases or removal