Fish for a good mood: How omega-3 helps the brain cope with stress Fatty fish can be good not only for your heart, but also for your mental health. A study found a link between high levels of omega-3 in the blood and a lower incidence of depression and anxiety. Omega 3 supports the transmission of signals between brain cells, and the protein is involved in the production of serotonin, dopamine and norepinephrine - substances that affect mood and motivation. Experts advise to regularly include fish and seafood in the diet, and alternate them with chicken, eggs, cottage cheese and legumes. For a full lunch you should also add carbohydrates and vegetables.