Both (n-3) long-chain PUFA (LCPUFA) and linoleic acid [LA, 18:2(n-6)] improve cardiovascular disease (CVD) risk factors, but a high-LA intake may weaken the effect of (n-3) LCPUFA. In a controlled, double-blind, 2 x 2-factorial 8-wk intervention, we investigated whether fish oil combined with a high- or low-LA intake affects overall CVD risk profile.

Healthy men (n = 64) were randomized to 5 mL/d fish oil capsules (FO) [mean intake 3.1 g/d (n-3) LCPUFA] or olive oil capsules (control) and to oils and spreads with either a high (S/B) or a low (R/K) LA content, resulting in a 7.3 g/d higher LA intake in the S/B groups than in the R/K groups. Diet, (n-3) LCPUFA in peripheral blood mononuclear cells, blood pressure (BP), heart rate (HR), and plasma CVD risk markers were measured before and after the intervention.

FO lowered fasting plasma triacylglycerol (TAG) (P < 0.001) by 51% and 19% in the FO+R/K-group and FO+S/B-group, respectively, which was also reflected in postprandial TAG measured after the intervention (P < 0.01).

Although a fat x FO interaction was found for monocyte chemoattractant protein-1, neither the FO nor fat intervention affected fasting plasma cholesterol, glucose, insulin, fibrinogen, C-reactive protein, interleukin-6, vascular cell adhesion molecule-1, P-selectin, oxidized LDL, cluster of differentiation antigen 40 ligand (CD40L), adiponectin, or fasting or postprandial BP or HR after adjustment for body weight changes.

In conclusion, neither fish oil supplementation nor the LA intake had immediate pronounced effects on the overall CVD risk profile in healthy men, but fish oil lowered plasma TAG in healthy subjects with initially low concentrations.

PMID: 18492834

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