Fish lipids contain a higher proportion of n-3 long chain highly unsaturated fatty acids (LCHUFA) than other animals. Fish is the primary source of n-3 LC-HUFA such as eicosapentaenoïc acid (EPA C20:5 n-3) and docosahexaenoïc acid (DHA C22:6 n-3) in human food. Because of limitations of fisheries capture, the supply of fish market with products from fish farming is growing. Unlike fisheries products, fish from farming can be tailored through rearing practices. Changes in n-3 LC-HUFA of fish flesh can be achieved either directly by feeding fish with diets rich in fish oil or indirectly by increasing muscle fat content through feeding manipulations (ration size, feed energy content) and genetic selection. The addition of vitamin E as an antioxidant in fish feed increases the levels of vitamin E in muscle, which prevents LC-HUFA from peroxidation.