DHA mediates the protective effect of fish consumption on new episodes of depression among women

Journal article

In a longitudinal cohort study of young Australian adults, we reported that for women higher baseline levels of fish consumption were associated with reduced incidence of new depressive episodes during the 5-year follow-up. Fish are high in both n-3 fatty acids and tyrosine. In this study, we seek to determine whether n-3 fatty acids or tyrosine explain the observed association. During 2004-2006, a FFQ (nine fish items) was used to estimate weekly fish consumption among 546 women aged 26-36 years. A fasting blood sample was taken and high-throughput NMR spectroscopy was used to measure 233 metabolites, including serum n-3 fatty acids and tyrosine. During 2009-2011, new episodes of depression since baseline were identified using the lifetime version of the Composite International Diagnostic Interview. Relative risks were calculated using log-binomial regression and indirect effects estimated using the STATA binary_mediation command. Potential mediators were added to separate models, and mediation was quantified as the proportion of the total effect due to the mediator. The n-3 DHA mediated 25·3 % of the association between fish consumption and depression when fish consumption was analysed as a continuous variable and 16·6 % when dichotomised (reference group: <2 serves/week). Tyrosine did not mediate the association (<0·1 %). Components in fish other than n-3 fatty acids and tyrosine might be beneficial for women's mental health.

Authors: Reeves, J; Otahal, P; Magnussen, C; Dwyer, T; Kangas, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Cambridge University Press
• Journal: British Journal of Nutrition
• Volume: 118
• Issue: 9
• Pages: 743-749
• Publication date: 2017-11-14
• Acceptance date: 2017-09-15
• DOI: 10.1017/s0007114517002768
• EISSN: 1475-2662
• ISSN: 0007-1145
• Pmid: 29185935
• Language: English
• Keywords: diet; young adults; mental Health; seafood; follow-up studies; metabolomics; depression; animals; longitudinal studies; docosahexaenoic acids; fishes; Australia; tyrosine; fish; n-3 fatty acids; incidence; fatty acids, omega-3