On the other hand, if they are fed grain, their Omega-3 levels crash. Wild game is much healthier to eat and it is much leaner than farm-raised animals. These have been replaced primarily with grains, which contain the wrong kinds of fats. There are many things that can interfere with this process, especially vegetable oils in the diet. Note that it is possible to acquire EPA and DHA directly by eating fish oil, certain eggs, or by taking supplements.
Fatty fish contain plenty of both substances.
Plenty of studies have shown that fish-eating cultures have much better health, including mental health. DHA is particularly important for brain functions. Scientists have discovered that severely depressed people are lower in DHA, and the more depressed they are, the less DHA they have. One ancient remedy for depression was to feed the patient animal brains, now known to be extremely high in DHA and Omega-3 fatty acids. Incidentally, alcohol is known to deplete DHA stores extremely rapidly.