This study aims to investigate the effect of habitual oily fish intake as well as sex, age, BMI, and Apolipoprotein E (APOE) genotype on LC n-3 PUFA status in plasma phosphatidylcholine, non-esterified fatty acids, cholesteryl esters and triacylglycerols in order to obtain greater knowledge of the determinants of LC n-3 PUFA status with the potential to develop more robust, and perhaps subgroup specific, recommendations for EPA and DHA intake.