Feeling down? Spoon up some fish. Seafood is full of omega-3 fatty acids, compounds that are essential building blocks for brain cells. Their healthy fats also help regulate mood, allowing the "feel-good" brain chemicals, serotonin and dopamine, better entry into the cells. Omega-3s EPA and DHA also help prevent inflammation in the brain, which "contributes to the development of depression" according to Gordon Parker, M.D., Ph.D., Executive Director of the Black Dog Institute, a research institute specializing in mood disorders. To nab the benefit, he says, "it's suggested to eat at least 2 servings of oily fish (e.g. salmon, blue mackerel) per week."