Stress and fatty liver--possible indications for dietary long-chain n-3 fatty acids.

The favourable effects of eicosapentaenoic acid (EPA)- and doco-sahexaenoic acid (DHA)-rich diets (marine fish, fish oil) on several risk factors for cardiovascular disease are well established. The present survey describes possible new indications for diets supplemented with long-chain n-3 fatty acids. During a standardized psychophysiological stress test (arithmetic, sentence completion tasks) systolic blood pressure after 2 weeks of diets supplemented with either 60 ml/day of sunflower or linseed oil was significantly decreased. During the sunflower oil-rich diet 45 g/day of linoleic acid (LA) and during the linseed oil-rich period 38 g/day of alpha-linolenic acid (LNA) were ingested. After a 2-week diet supplemented with mackerel (2 cans/day equivalent to 2.2 g/day of EPA and 2.8 g/day of DHA) systolic and diastolic blood pressure within the same test design appeared significantly lower. After a herring diet providing 2 cans/day, equivalent to 1.0 g of EPA and 1.8 g of DHA, the blood pressure-lowering effect was minor. The increase of thromboxane B2 (TxB2) during the stress test failed to occur after the fish diets. The results suggest a stress-protective effect of polyenoic acid-rich diets, which appears most pronounced and dose-related after long-chain n-3 fatty acids. In human liver an increase of fat droplet size in hepatocytes is associated with a decrease of the percentage of EPA in liver triglycerides. A diminution of plasma free fatty acids (FFA) after a mackerel diet might contribute to a depressed synthesis of liver triglycerides.(ABSTRACT TRUNCATED AT 250 WORDS)