The atherosclerotic risk profile is affected differently by fish flesh with a similar EPA and DHA content but different n-6/n-3 ratio

The aim of this study was to evaluate the effect of consuming gilthead sea bream fillets, with different n-6/ n-3 ratios, on atherosclerotic biomarkers. Twenty healthy subjects were included in a randomised single-blinded cross-over trial. Participants were randomized into 2 groups, both of which received approximately 630 g per week of gilthead sea bream fed with either 100% fishmeal (FM) or partial replacement with plant proteins (PP) over two consecutive 10 week periods, respectively. Group A consumed firstly the FM fillets followed by the PP fillets, whereas the reverse order was adopted for group B. Group A reported a significant decrease of 29.3% (∆ = –26 mg/dL) in total cholesterol after the first phase of the intervention, before returning to baseline levels after the dietary intervention with fish fed with PP. Similarly, in group A, both LDL-cholesterol and triglycerides decreased significantly by 21.6% (∆ = –19 mg/dL) and 11.7% (∆ = –10.7 mg/dL), respectively, before increasing again after the intervention. Improvements in the inflammatory cytokines, interleukin-6 and -8 were also noted. Moreover, whole blood viscosity appeared significantly improved in group A, as seen by a significant increase of 7.59% (∆ = +4.59 mPA) for erythrocyte filtration rate. In conclusion, similar EPA+DHA content with different n6/n-3 ratio fish flesh intake was shown to have varied affects on lipid, inflammatory and haemorheological parameters in a group of healthy subjects.