Dietary intake of long chain omega-3 poly-unsaturated fatty acids (LC n-3 PUFAs) in developed countries is low compared to recommendations. Seafood is naturally rich in LC n-3 PUFAs, vitamin D, and iodine, but is also a dietary source of heavy metals and organic pollutants. This study investigated the current intake of selected nutrients and contaminants via seafood and studied whether the recommendation for LC n-3 PUFAs could be reached through seafood consumption, without exceeding tolerable daily intakes (TDIs) of methyl mercury (MeHg) and dioxin-like compounds. Also the contribution of LC n-3 enriched margarines was assessed. On the basis of the current seafood consumption data, the simulation results predicted that the population currently does not reach an adequate intake for the three nutrients considered, at least when only seafood consumption is accounted for. This is mainly due to low frequency of seafood consumption. Regarding the contaminants, MeHg contamination in seafood assumed to be available on the Belgian market is not a major issue. In contrast, exceeding the TDI was noticed for the intake of dioxin-like compounds and this for heavy seafood consumers. Combination of regular seafood consumption (twice a week), with important contribution of fatty fish species (at least 50%), with regular consumption of EPA plus DHA enriched margarine can be advised to maximize LC n-3 PUFA intake without exceeding the TDI for dioxin-like compounds. It is important to add that no other dietary sources of dioxin-like compounds were taken into account in this assessment.