In June 2018 researchers from Spain and the USA published the results of their study to assess the association between fish and seafood consumption and long chain omega-3 polyunsaturated fatty acid intake and depression in 6,587 individuals. Information on fish and seafood consumption and omega-3 polyunsaturated fatty acid intake was collected via a validated food-frequency questionnaire, and information on depression was self-reported (life-time medical diagnosis of depression or use of antidepressants). Out of 6,587 participants, there were 1,367 cases of depression. Results showed that total seafood consumption did not appear to be associated with depression. However, a further analysis revealed that the lowest incidence of depression was seen to occur with a moderate consumption of fatty fish, as opposed to a low or high consumption (a “U”-shaped association). In addition, a moderate intake of total long chain omega-3 polyunsaturated fatty acids intake (approximately 0.5-1 g/day) was significantly associated with a lower incidence of depression.
Sánchez-Villegas A et. Seafood Consumption, Omega-3 Fatty Acids Intake, and Life-Time Prevalence of Depression in the PREDIMED-Plus Trial. Nutrients. 2018 Dec 18;10(12).