In the case of salmon, the answer is yes. Salmon are fantastic sources of DHA, the omega-3 fatty acid that is essential for brain development, which they also get from phytoplankton. DHA is stored in salmon’s fat, most often in the belly, and a 4-ounce serving of salmon can dish up 2,400 mg omega-3s. Larger species, such as king, and those which have longer upstream journeys, tend to store more fat and have more omega-3s. Farmed salmon are often fattier than wild salmon, but that’s because they are fed a diet that includes grains and vegetable oils that are high in omega-6 fats, which combat the beneficial effects of omega-3s. However, the higher fat content (often as high as 16 percent versus 8 percent for wild fish) means the fish is easier to cook and retains its moistness.