An increased dietary intake of n-3 highly unsaturated fatty acids (HUFA; >or=20 carbons, >or=3 carbon-carbon double bonds), particularly eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), is associated with the decreased risk and incidence of several morbidities afflicting the elderly, including cognitive decline, dementia, rheumatoid arthritis, and macular degeneration. In this study, the dietary intake and blood levels of fatty acids were directly determined in residents of a retirement home or assisted living phase of a continuum of care facility for Canadian seniors. Finger-tip-prick blood samples, 3-day food duplicates, and 3-day food records were collected. The fatty acid composition of food duplicates and blood was determined by gas chromatography. Fifteen participants (7 male, 8 female; 87.1 +/- 4.8 years of age) completed the protocol. The daily intake of EPA and DHA combined, determined directly, was 70 mg (95% CI, 41-119) or 0.036% of total energy (95% CI, 0.022-0.058). In finger-tip-prick blood, the percent of n-3 HUFA in total HUFA of whole blood, a biomarker of n-3 polyunsaturated fatty acid status, was 28.8 +/- 5.2%. Correlations between daily n-3 HUFA intake and n-3 HUFA in blood were not significant (r = 0.14; n = 15), but became significant after the removal of 2 participants who appeared to consume fish irregularly (r = 0.59; n = 13). The n-3 HUFA intake and corresponding n-3 HUFA blood levels of Canadian long-term care residents are lower than levels estimated to prevent several morbidities associated with aging.

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Intakes of 250–500 mg/d of eicosapentaenoic acid (EPA, 20:5n‐3) and docosahexaenoic acid (DHA, 22:6n‐3) have been proposed for health benefits. There is little data examining the response of omega‐3 blood biomarkers to these dietary intakes as most intervention studies use higher doses of EPA+DHA. Presently, we examine the blood biomarker response of men (n=11) and women (n=10) after the consumption of 250mg/d of EPA+DHA and 500mg/d EPA+DHA for 4 week periods. Erythrocytes and plasma were collected at baseline, week 4 and week 8 and fingertip prick whole blood was collected weekly. Intake of EPA+DHA at baseline was 72±51mg/d as determined by food frequency questionnaire validated for n‐3 HUFA (highly unsaturated fatty acids, ≥20 carbons, ≥3 carbon‐carbon double bonds). Baseline %n‐3 HUFA in total HUFA was 24.0±2.0 and 22.3±3.3 in venous erythrocytes and plasma, respectively. Initial results show the %n‐3 HUFA in total HUFA in fingertip prick whole blood increased from 22.1±2.1% at baseline to 24.3±1.6% at week 1 and to 25.2±1.9% at week 2 (p<0.01). These results will indicate if 250–500mg/d of EPA+DHA can increase blood levels of EPA+DHA to levels associated with the prevention of sudden cardiac death. Supported by a doctoral research award (ACP) from the Canadian Institutes of Health Research.