Higher Increases in Plasma n‐3 Polyunsaturated Fatty Acids Following Fish Oil Supplementation in Postmenopausal Females Compared With Age‐Matched Males

The effects of fish oil supplementation on omega-3 (n-3) polyunsaturated fatty acids, particularly intermediates between eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), that may provide valuable metabolic information, have not been fully characterized in older populations. A total of 10 postmenopausal females (69.6 ± 2.6 years, mean ± SEM) and 10 age-matched males (70.0 ± 2.4) were supplemented with fish oil (1.8 g/day EPA and 1.4 g/day DHA) for 5 months, and blood was collected to determine n-3 PUFA levels. Significant interaction effects (sex × supplementation) for plasma phospholipid EPA, DHA, and 24:5n-3 (p < 0.05) revealed 69%, 101%, and 182% higher levels, respectively, in females compared with males post-supplementation. Significant main effects of supplementation yielded 83%-327% higher plasma triacylglycerol EPA, DHA, 22:5n-3, and 24:5n-3 (p < 0.05) post-supplementation. Our findings provide insight into sex-dependent DHA metabolism in healthy older adults, which may help inform more targeted EPA and/or DHA supplementation advice to promote improved n-3 PUFA status.