Hypertriglyceridemia is an important risk factor for coronary heart disease (CHD) and in the development of atherosclerosis, especially in subgroups of the population like those with type 2 diabetes. Although triglycerides are generally increased in the postprandial period, the association between postprandial triglyceride (ppTG) levels and atherosclerosis has not been investigated in north Indian type 2 diabetic subjects known to have a very high prevalence rate of premature CHD and insulin resistance. To investigate the role of ppTG levels in atherosclerosis in type 2 diabetes, we examined the correlation between ppTG levels and carotid intima-media thickness (IMT). Carotid IMT was determined by high resolution B-mode ultrasonography in 86 newly detected type 2 diabetic subjects (1-12 months duration) having good glycemic control (HbA(1C)<7%) and 45 non-diabetic subjects matched according to age and body mass index (BMI). Plasma glucose, insulin, total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides were measured after overnight fasting. Plasma insulin and glucose were also measured 2h and plasma triglycerides 4h after breakfast. The mean carotid IMT in diabetic subjects was higher than those in non-diabetic subjects (0.77+/-0.15 mm versus 0.53+/-0.16 mm, P<0.001). Based on the fasting and postprandial triglyceride levels, the diabetic subjects were divided into three groups: normo-normo (NN); normo-hyper (NH); hyper-hyper (HH) [NN: fTG<1.70 mmol/L and ppTG<2.30 mmol/L; NH: fTG<1.70 mmol/L and ppTG>2.30 mmol/L; HH: fTG>1.70 mmol/L and ppTG>2.30 mmol/L]. Carotid IMT was significantly increased in the NH (0.79+/-0.09 mm) and HH (0.82+/-0.06 mm) groups compared with the NN group (0.59+/-0.09 mm, P<0.001). Although ppTG, age, fasting LDL-cholesterol, HOMA-estimated insulin resistance, HbA(1C) were all independently correlated with carotid IMT, age and ppTG levels had the strongest statistical influence (P<0.002).