EFFECT OF LOW GLYCEMIC INDEX DIET ON APOLIPOPROTEIN B AND LDL PARTICLE SIZE

Abstract

BackgroundApolipoprotein B (Apo B) and small LDL particles have been strongly associated with increased coronary artery disease while low glycemic index diets (GI) may reduce risk. We have therefore assessed the effect of consumption of a low GI diet on Apo B and LDL particle size.Methods155 type 2 diabetic subjects treated with antihyperglycemic agents were randomized and completed either 6 months of high fiber or low glycemic index dietary advice in a parallel design. Serum samples were obtained pre‐treatment and at the end of the 6 month study period.ResultsThere was no significant treatment difference in Apo B but a significant reduction in estimated small dense LDL cholesterol (sdLDL‐C) on the low GI diet by ‐0.15 ± 0.08 mmol/L compared to the high fiber diet (p=0.048). No significant treatment differences were seen in LDL particle size distribution. Dietary glycemic load, not glycemic index, correlated positively to serum levels of sdLDL‐c (Rho=0.17, p=0.036), while correlated negatively with serum levels of medium LDL particles (Rho=‐0.17, p=0.042) and large LDL particles (Rho=‐0.18, p=0.026).ConclusionThese findings suggest a benefit of low glycemic index diets in reduction of sdLDL‐c levels in type 2 diabetes.Funding Canadian Institutes of Health Research, Canada Research Chair Endowment of the Federal Government of Canada, and Barilla (Italy).