Effect of Fish Oil Versus Corn Oil Supplementation on LDL and HDL Subclasses in Type 2 Diabetic Patients

Abstract

OBJECTIVE—The increased risk of coronary heart disease associated with type 2 diabetes may be partially explained by dyslipidemia characterized by high plasma triacylglycerol (TAG), low HDL cholesterol, and a predominance of atherogenic small dense LDLs. Fish oil reduces plasma TAG and has previously been shown to improve the distribution of LDL subclasses in healthy subjects and might, therefore, be a good nonpharmacological treatment for type 2 diabetic patients. In the present study, we investigate the effect of fish oil supplementation on the fasting lipid profile, including LDL and HDL subclasses. RESEARCH DESIGN AND METHODS—A total of 42 type 2 diabetic patients were randomized to supplementation (capsules) with 4 g daily of either fish oil (n = 20) or corn oil (n = 22) for 8 weeks preceded by a 4-week run-in period of corn oil supplementation. Blood was drawn before and after the 8-week intervention period. Plasma lipoproteins, including LDL and HDL subclasses, were separated by ultracentrifugation. RESULTS—Fish oil lowered TAG (group difference: P = 0.025) and raised HDL-2b cholesterol (P = 0.012) and HDL-2a cholesterol (P = 0.007) concentrations as compared with corn oil. We observed no significant effects of fish oil on LDL cholesterol, HDL cholesterol, or the concentration of small dense LDL particles. CONCLUSIONS—Fish oil supplementation may partially correct the dyslipidemia of type 2 diabetic patients. However, the putative very important aspect of diabetic dyslipidemia—the predominance of small dense LDL particles—was unaffected by fish oil.

Effects of marine n-3 fatty acid supplementation on lipoprotein subclasses measured by nuclear magnetic resonance in subjects with type II diabetes

“…Others have reported no effect of n-3 FA in subjects with type II diabetes (Luo et al, 1998) or a tendency to a smaller increase than in a control group (Petersen et al, 2002). Reduction of small HDL was observed in one report, but this effect was seen only with intervention of EPA, not with DHA (Woodman et al, 2002).…”

“…The reductions of VLDL size and reduced concentration of large VLDL that we observed have, to our knowledge, not been previously reported. Others have reported no change in the distribution of VLDL subclasses in subjects with type II diabetes (Patti et al, 1999) or did not measure these subclasses (Petersen et al, 2002). Reduction of VLDLcholesterol, on the other hand, is well documented but mainly in the setting of a concomitant lowering of triglycerides (Harris et al, 1983;Malasanos and Stacpoole, 1991;Connor, 2000;Montori et al, 2000).…”

“…It is therefore important to investigate effects of n-3 FA on subclasses and size of lipoproteins in subjects with type II diabetes (Syvänne and Taskinen, 1997;Julius, 2003;Steinmetz, 2003). However, such investigations in diabetes by standard methods (ultracentrifugation, gradient gel electrophoresis) have so far given sparse and diverging results (Luo et al, 1998;Patti et al, 1999;Petersen et al, 2002). Measurements using nuclear magnetic resonance (NMR) relate to the severity of cardiovascular disease (Freedman et al, 1998) and could provide needed details of lipoprotein size and subclasses (Otvos, 2002).…”

Meta-analysis of the effects of n-3 polyunsaturated fatty acids on lipoproteins and other emerging lipid cardiovascular risk markers in patients with type 2 diabetes

“…The trials included in the pooled analyses were small, with a median of 23 patients. Seventeen of the published papers were duplicate publications of six trials [22, 27, 33, 34, 36-38, 40, 42-46, 48, 51, 54, 55]; multiple papers for each trial are indicated by the following grouping of references: [22,38], [27,34,36,37], [40,54,55], [42,48,51], [43,46], [44,45]. There was sufficient information on only 12 of the 98 outcomes to allow data to be pooled, the results of which are shown in Fig.…”

“…4). Four trials reported changes in HDL-3 among 114 nonhypertriacylglycerolaemic subjects [32,46,47,54]. n-3 PUFA supplementation non-significantly decreased HDL-3 by 0.02 mmol/l (95% CI −0.07 to 0.03; p=0.42) (ESM Fig.…”