Effect of Eicosapentaenoic and Docosahexaenoic Acids on Blood Pressure in Hypertension

Abstract

Studies of whether polyunsaturated fatty acids in fish oil--in particular, eicosapentaenoic and docosahexaenoic acids--lower blood pressure have varied in design and results. We conducted a population-based, randomized, 10-week dietary-supplementation trial in which the effects of 6 g per day of 85 percent eicosapentaenoic and docosahexaenoic acids were compared with those of 6 g per day of corn oil in 156 men and women with previously untreated stable, mild essential hypertension. The mean systolic blood pressure fell by 4.6 mm Hg (P = 0.002), and diastolic pressure by 3.0 mm Hg (P = 0.0002) in the group receiving fish oil; there was no significant change in the group receiving corn oil. The differences between the groups remained significant for both systolic (6.4 mm Hg; P = 0.0025) and diastolic (2.8 mm Hg; P = 0.029) pressure after control for anthropometric, lifestyle, and dietary variables. The decreases in blood pressure were larger as concentrations of plasma phospholipid n-3 fatty acids increased (P = 0.027). Dietary supplementation with fish oil did not change mean blood pressure in the subjects who ate fish three or more times a week as part of their usual diet, or in those who had a base-line concentration of plasma phospholipid n-3 fatty acids above 175.1 mg per liter. We conclude that eicosapentaenoic and docosahexaenoic acids reduce blood pressure in essential hypertension, depending on increases in plasma phospholipid n-3 fatty acids.

Hypertension prevention: from nutrients to (fortified) foods to dietary patterns. Focus on fatty acids

“…Other studies with very low doses reported (150 mg DHA and 30 mg EPA) a positive effect on systolic pressure but no effect on diastolic blood pressure. 32 The clinical investigations in humans tend to confirm the hypothesis that o3 PUFAs display antihypertensive properties, 25,30,[32][33][34] in spite of some discrepancies. 35,36 In a meta-analysis, Morris et al 31 outlined the variability of experimental factors (dose, group size, duration of the experiment and patient selection) as a major cause of discrepancy.…”

“…30 A high dose supplement with long-chain o3 PUFAs (3-9 g/day) reduces significantly both systolic and diastolic pressure in patients with a moderate hypertension. Similarly, in an intervention study on a group declaring not to consume any fish and displaying a moderate hypertension (systolico180, diastolico110), a fish oil supplement (6 g/day, representing 5 g of EPA þ DHA) reduced significantly both systolic and diastolic blood pressure.…”

Serum phospholipid fatty acid composition and habitual intake of marine foods registered by a semi-quantitative food frequency questionnaire

“…The samples were centrifuged and serum separated and transferred to te¯on lined screwcapped vials within 1±4 h. Serum samples were kept at 4 C for 2±6 h before delivered to the Regional Hospital, University of Trondheim, and stored at 780 C until analysed. The serum phospholipids fatty acids were analysed essentially as described previously (Bùnaa et al, 1990). Serum lipids were extracted with n-butanol (Bjerve et al, 1974) and phospholipids isolated from the lipid extracts using Sep-Pack C18 columns.…”

Intake of very-long-chain n-3 fatty acids related to social status and lifestyle

“…The intake of very-long-chain n-3 fatty acids is described in clinical trials (Bùnaa et al, 1990;Sùyland et al, 1994;Brude et al, 1997), selected groups (Bang et al, 1980;Tjùnneland et al, 1993;Nydahl et al, 1996;Hjartaker et al, 1997) and prospective studies (Morris et al, 1995;Ascherio et al, 1995;Dolecek, 1992;Pietinen et al, 1997), but little information is available about the intake of very-long-chain n-3 fatty acids in random samples of populations (Steingrimsdottir et al, 1995). We therefore assessed the intake and sources of very-long-chain n-3 fatty acids and related the intake to socio-demographic and life-style variables in a national dietary survey.…”