Background Regular consumption of dietary fish and n-3 polyunsaturated fatty acids (PUFA) of marine origin can lower blood pressure levels and reduce cardiovascular risk. However the contribution of each n-3 and n-6 PUFA to blood pressure regulation is still controversial. The aim of our study was to estimate the relationship between blood pressure level and proportions of n-3 and n-6 PUFA in plasma and erythrocytes in healthy males.
Material and methods We studied 21 male subjects (mean age 58,5 ± 9 years) during their routine medical checkups. Systolic (SBP 134,8 ± 19 mm Hg), diastolic (DBP 84,0 ± 10 mm Hg) and mean (MAP 100,9 ± 12 mm Hg) blood pressure was calculated as the mean from two measurements performed six years apart. PUFA n-3 and n-6 in plasma and erythrocytes were determined by gas-liquid chromatography.
Results Among erythrocyte fatty acids only C20:5 n-3 PUFA was significantly inversely associated with mean DBP (r = –0,44, p < 0,05). Among plasma fatty acids we found an inverse association between SBP, DBP and MAP with the sum of n-3 PUFA: C18:4, C20:4, C20:5, C22:5, C22:6 (r = –0,57, p < 0,02; r = –0,65, p < 0,01 and r = –0,62, p < 0,01 for SBP, DBP and MAP respectively) and the sum of n-6 PUFA; C18:3; C20:3; C20:4; C22:4; C22:5 (r = –0,63, p < 0,01; r = –0,67, p < 0,01; r = –0,66, p < 0,005 for SBP, DBP and MAP respectively). There was also correlation between DBP and plasma concentration of eikosapentaenoic acid (EPA) C20:5 (r = –0,51, p < 0,05).
Conclusions Our findings are consistent with the hypothesis that plasma and erythrocyte n-3 and n-6 polyunsaturated fatty acids composition affect blood pressure level in healthy males.