Dietary Mono- and polyunsaturated fatty acids similarly affect LDL size in healthy men and women.
Dietary Mono- and polyunsaturated fatty acids similarly affect LDL size in healthy men and women.
Year: 2002
Authors: M Kratz, E G?lbah?e, A Eckardstein, P Cullen, A Gignarella, G Assmann, U Wahrburg.
Publication Name: J Nutr
Publication Details: Volume 132; Page 715
Abstract:
In both normal and hyperlipidemic individuals, LDL particles differ considerably in size, density and composition. Small, dense LDL subclass has been associated with an increased risk of coronary heart disease (CHD) in cross-sectional and case-control studies. Observations in patients with CHD suggest that the association between small, dense LDL and cardiovascular diseases is due to confounding by other lipoprotein-related risk factors and the relationship is not fully understood. Small, dense LDL subspecies exhibit several properties that render them more atherogenic than large, buoyant LDL particles including a reduced affinity for the LDL receptor, which results in a prolonged plasma half-life, an increased affinity for receptor-independent cell-surface binding sites and LDL depositation in the arterial wall. The effect of dietary fat quality on LDL size has not been the scope of a controlled dietary study. This study investigated the effect of the dietary fatty acid composition on LDL peak particle diameter in healthy volunteers and was designed initially to investigate the effect of refined olive oil (rich in MUFA), rapeseed oil [rich in MUFA and (n-3)-PUFA], and sunflower oil [rich in (n-6)-PUFA] on LDL susceptibility to oxidation. LDL size from 56 (30 men, 26 women) healthy participants were measured following a controlled dietary study. All participants received a baseline diet rich in saturated fat for 2 wk; they were then randomly assigned to one of three dietary treatments, which contained refined olive oil [rich in monounsaturated fatty acids (MUFA), n = 18], rapeseed oil [rich in MUFA and (n-3)-ALA (PUFA), n = 18], or sunflower oil [rich in (n-6)-PUFA, n = 20] as the principal source of fat for 4 wk. A small, but significant reduction in LDL size during the oil diet phase, which did not differ significantly among the three groups, was noted. In conclusion, the data indicate that dietary unsaturated fat similarly reduces LDL size relative to saturated fat. Given the wide differences in the fatty acid compositions of the diets, the observed changes and differences were surprisingly small and had only a modest effect on LDL size. It is unknown whether these changes would have any clinical implications in particular CHD risk. Furthermore, the small magnitude of this reduction suggests that the composition of dietary fat is not a major factor affecting LDL size.
