Increased alpha-linolenic acid intake lowers C-reactive protein, but has no effect on markers of atherosclerosis.

ABSTRACT

OBJECTIVE: To investigate the effects of increased alpha-linolenic acid (ALA)-intake on intima-media thickness (IMT), oxidized low-density lipoprotein (LDL) antibodies, soluble intercellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and interleukins 6 and 10. DESIGN: Randomized double-blind placebo-controlled trial. SUBJECTS: Moderately hypercholesterolaemic men and women (55 +/- 10 y) with two other cardiovascular risk factors (n = 103). INTERVENTION Participants were assigned to a margarine enriched with ALA (fatty acid composition 46% LA, 15% ALA) or linoleic acid (LA) (58% LA, 0.3% ALA) for 2 y. RESULTS: Dietary ALA intake was 2.3 en% among ALA users, and 0.4 en% among LA users. The 2-y progression rate of the mean carotid IMT (ALA and LA +0.05 mm) and femoral IMT (ALA+0.05 mm; LA+0.04 mm) was similar, when adjusted for confounding variables. After 1 and 2 y, ALA users had a lower CRP level than LA users (net differences -0.53 and -0.56 mg/l, respectively, P < 0.05). No significant effects were observed in oxidized LDL antibodies, and levels of sICAM-1, interleukins 6 and 10. CONCLUSIONS: A six-fold increased ALA intake lowers CRP, when compared to a control diet high in LA. The present study found no effects on markers for atherosclerosis. SPONSORSHIP The Dutch 'Praeventiefonds'.