Influence of dietary cod liver oil on fatty acid composition of plasma lipids in human male subjects after myocardial infarction.

A randomized crossover study was carried out to investigate the fatty acid profile and concentrations of plasma lipids in male patients with myocardial infarction (MI) who supplemented their diet with 20 ml cod liver oil daily for 6 weeks. Subjects were divided into two groups, A and B. Group A received cod liver oil daily for 6 weeks after hospital discharge, but none for the subsequent 6 weeks. Group B did not start taking cod liver oil until 6 weeks after hospital discharge, and they then took cod liver oil for 6 weeks. Diet, medication or smoking habits were kept as constant as possible during the study. During the period of cod liver oil intake, eicosapentaenoic acid (20:5 (n-3), EPA) and docosahexaenoic acid (22:6 (n-3), DHA) increased significantly in phospholipids (PL), triglycerides (TG) and cholesterol esters (CE), whereas linoleic acid (18:2 (n-6), LA), dihomo-gamma-linolenic acid (20:3 (n-6), DHGLA) and arachidonic acid (20:4 (n-6), AA) were significantly decreased in phospholipids. The plasma level of TG was significantly decreased during the cod liver oil intake. Total cholesterol, high density lipoprotein (HDL) cholesterol, and levels of apolipoproteins A1 and B were not affected by cod liver oil in these MI patients.

Cod liver oil does not reduce ventricular extrasystoles after myocardial infarction.

Previous work has shown that in experimental animal models a lower incidence of arrhythmias and sudden death was observed if the animals were fed cod liver oil or fish oil. After a 48-h control period starting, on average, 8 days after the onset of symptoms, 18 men who were recovering from acute myocardial infarction were given 20 ml d-1 cod liver oil for 6 weeks, either immediately after the control period, weeks 0-6 (n = 10), or during weeks 6-12 (n = 8). Forty-eight-hour Holter monitoring was carried out before cod liver oil administration and at the end of weeks 6 and 12. The eicosapentaenoic acid content of plasma phospholipids was increased by 230% during cod liver oil administration. However, no significant change was observed in the 24-h prevalence of ventricular extrasystoles or other arrhythmias during the study period. The mean ln number of ventricular extrasystoles was 2.95 +/- 0.51 (+/- SEM) during cod liver oil ingestion and 2.63 +/- 0.30 when not taking cod liver oil.