A high carbohydrate versus a high monounsaturated fatty acid diet lowers the atherogenic potential of big VLDL particles in patients with type 1 diabetes

The objective of the present study was to compare the effects of two diets on the atherogenic potential of two VLDL subfractions harvested from fasting subjects by measuring the number and composition of particles and the amount of esterified cholesterol accumulated in macrophages. A high (25%) monounsaturated fatty acid (Mono) diet and a high (61%) carbohydrate (CHO) diet were provided for 4 wk in a randomized crossover design to 19 normolipidemic, nonobese patients with type I diabetes. The two diets were matched for protein, polyunsaturated/saturated fatty acids, cholesterol and fiber content. The number of circulating big VLDL (S(f) 100-400) particles was greater during the high Mono than during the high CHO diet based on the levels of apolipoprotein B (means ± SEM): 31.4 ± 7.4 versus 20.0 ± 3.8 mg/L (P < 0.025, paired t test). The following variables did not differ during the diet periods: number of small VLDL (S(f) 20-100) particles, esterified cholesterol accumulated in THP-1 macrophages incubated with the same number of big and small VLDL particles and particle composition. We conclude that a high CHO diet might be preferable to a high Mono diet, on the basis of the premise that more big VLDL particles could increase the atherosclerotic risk in patients with diabetes.