VERY-LONG-CHAIN N-3 FATTY-ACIDS AS BIOMARKERS FOR INTAKE OF FISH AND N-3 FATTY-ACID CONCENTRATES

We examined how supplementation with very-long-chain n-3 fatty acids w as reflected in the concentration of these fatty acids in plasma phosp holipids of 363 Norwegian men and women. The concentration of eicosape ntaenoic acid (EPA) and docosahexaenoic acid (DHA) in plasma phospholi pids was significantly higher among individuals supplemented with n-3 fatty acids after the supplementation period than before. We also exam ined the relation between dietary intake of fatty acids measured with a 180-item quantitative food-frequency questionnaire and the concentra tion of the same fatty acids in plasma phospholipids in 579 men and wo men. Correlation coefficients between plasma phospholipid fatty acids and dietary intake of fatty acids were 0.51 and 0.49 for EPA and DHA, respectively. The correlation between fish intake and n-3 fatty acids in plasma phospholipids was 0.37. These results suggest that dietary i ntake measured with our food-frequency questionnaire may be used to pr edict the biological availability of some of the essential n-3 fatty a cids.