Moderate omega-3 consumption reduces the risk of depression


Over 20 hospitals throughout Spain are involved in the PREDIMED-Plus Project, which has enrolled over 6,800 participants. This is the largest research challenge in the field of nutrition yet to be carried out in the country. Its aim is to assess the effects of the Mediterranean diet on health. Although focussing mainly on cardiovascular problems, the study has for some time also provided data on other diseases.

One of these is depression, a disease that previous studies have associated with a dietary deficiency in long-chain omega-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

An analysis published in the journal ‘Nutrients’ uses data from the PREDIMED-Plus study to see whether fish and omega-3 fatty acid consumption can reduce the risk of depression.

Participants filled in a questionnaire on their dietary habits, history of depression and antidepressant medication.

The investigators detected 1,367 cases of the disease among the participants. Although fish and seafood consumption was not associated with a risk of depression, the study found that moderate ingestion of long-chain omega-3 did reduce the risk of depression.

However, the authors of the article warned that this beneficial effect was only observed with moderate doses of omega-3, between half a gram and a gram daily, while the benefit was lost if intake was too high.

Although it is not known why this positive effect is lost at high doses of omega-3, the authors think it may be because of other nutrients that counteract the beneficial effects, including omega-6 fatty acids. It might also be that some of the study participants with depressive symptoms increased their intake of omega-3 to improve their disease and this somehow altered the results of the research.



López-Miranda J, Estruch R, Bueno-Cavanillas A, Arós F, Tur JA, Tinahones FJ, Lecea O, Martín V, Ortega-Calvo M, Vázquez C, Pintó X, Vidal J, Daimiel L, Delgado-Rodríguez M, Matía P, Corella D, Díaz-López A, Babio N, Muñoz MÁ, Fitó M, García de la Hera M, Abete I, García-Rios A, Ros E, Ruíz-Canela M Martínez-González MÁ, Izquierdo M, Serra-Majem L. Seafood Consumption, Omega-3 Fatty Acids Intake, and Life-Time Prevalence of Depression in the PREDIMED-Plus Trial. Nutrients. 2018 Dec 18;10(12). pii: E2000. doi: 10.3390/nu10122000.

Yang, Y.; Kim, Y.; Je, Y. Fish consumption and risk of depression: Epidemiological evidence from prospective studies. Asia Pac. Psychiatry 2018, e12335.

Estudio PREDIMED Plus