Fatty acids, selenium, and vitamin B12 in chub mackerel (Scomber colias) as nourishment considering seasonality and bioaccessibility as factors

• Chub mackerel is a rich source of EPA, DHA, Se, & vitamin B12. • Fatty acid bioaccessibility percentages were usually high, being mostly above 60 % • Se bioaccessibility was 91-95 % & vitamin B12 bioaccessibility was 77-83 % • Based on bioaccessibility, meeting Se requirement would entail 107-114 g mackerel/day. • For EPA+DHA & vitamin B12, 15-51 g mackerel/day would meet nutrient needs. Chub mackerel ( Scomber colias ) is an underutilised fish abundant in the North Atlantic and a nutritious food with high docosahexaenoic acid (DHA), selenium (Se), and vitamin B12 contents, affected by seasonality. Hence, the bioaccessibility of fatty acid (FA), Se, and vitamin B12 in chub mackerel was studied. Daily consumptions of 51 g, 35 g, and 14 g of March, June, and October chub mackerel, respectively, would ensure EPA+DHA requirements. Vitamin B12 requirements would be met by daily consumptions of 15-18 g of chub mackerel. For Se, larger amounts would be needed, 126-133 g/day. For FA, bioaccessibility often exceeded 80 %. Additionally, Se and vitamin B12 bioaccessibilities were 91-95 % and 77-83 %, respectively. Thus, bioaccessibility-based consumption frequencies for meeting dietary requirements are similar to those above, being the highest consumption frequencies associated to Se requirements, 137-146 g/day. Chub mackerel proved to be an excellent source of bioaccessible essential nutrients.