Seafood consumption, omega-3 fatty acids intake, and life-time prevalence of depression in the PREDIMED-Plus trial

BACKGROUND: The aim of this analysis was to ascertain the type of relationship between fish and seafood consumption, omega-3 polyunsaturated fatty acids (ω-3 PUFA) intake, and depression prevalence. METHODS: Cross-sectional analyses of the PREDIMED-Plus trial. Fish and seafood consumption and ω-3 PUFA intake were assessed through a validated food-frequency questionnaire. Self-reported life-time medical diagnosis of depression or use of antidepressants was considered as outcome. Depressive symptoms were collected by the Beck Depression Inventory-II. Logistic regression models were used to estimate the association between seafood products and ω-3 PUFA consumption and depression. Multiple linear regression models were fitted to assess the association between fish and long-chain (LC) ω-3 PUFA intake and depressive symptoms. RESULTS: Out of 6587 participants, there were 1367 cases of depression. Total seafood consumption was not associated with depression. The odds ratios (ORs) (95% confidence intervals (CIs)) for the 2nd, 3rd, and 4th quintiles of consumption of fatty fish were 0.77 (0.63⁻0.94), 0.71 (0.58⁻0.87), and 0.78 (0.64⁻0.96), respectively, and p for trend = 0.759. Moderate intake of total LC ω-3 PUFA (approximately 0.5⁻1 g/day) was significantly associated with a lower prevalence of depression. CONCLUSION: In our study, moderate fish and LC ω-3 PUFA intake, but not high intake, was associated with lower odds of depression suggesting a U-shaped relationship.This research was funded by the Spanish Ministry of Health (Carlos III Health Institute) through the Fondo de Investigación para la Salud (FIS), which is co-funded by the European Regional Development Fund (grant numbers and corresponding codes: PI13/00673, PI13/00492, PI13/00272, PI13/01123, PI13/00462, PI13/00233, PI13/02184, PI13/00728, PI13/01090, PI13/01056, PI14/01722, PI14/00636, PI14/00618, PI14-00696, PI14/01206, PI14/01919, PI14/00853), the European Research Council (Advanced Research Grant 2013–2018; 340918) grant to MAMG, the Recercaixa grant to J. S-S. and NB (2013ACUP00194), the grant from the Consejería de Salud de la Junta de Andalucía (PI0458/2013; PS0358/2016), the SEMERGEN grant, and FEDER funds (CB06/03)