In the present study, we examined longitudinal changes in self-reported depressive symptoms (and related domains) in relation to baseline intakes of n-3 fatty acids (absolute and relative to n-6 fatty acids). Sex-specific associations were evaluated in a prospective cohort of adults (n = 2,053) from Baltimore, Maryland, who were 30-64 years of age at baseline and were followed for a mean of 4.65 (standard deviation, 0.93) years (2004-2013). Using mean intakes of n-3 and n-6 fatty acids reported on two 24-hour dietary recalls, we estimated the ratios of n-3 to n-6 fatty acids for both highly unsaturated fatty acids (≥20 carbon atoms) (HUFAs) and polyunsaturated fatty acids (≥18 carbon atoms) (PUFAs). Outcomes included total and domain-specific scores on the 20-item Center for Epidemiologic Studies-Depression scale. Based on mixed-effects regression models, among women, both higher n-3 HUFA:n-6 PUFA and n-3 PUFA:n-6 PUFA ratios were associated with a slower rate of increase in total Center for Epidemiologic Studies-Depression scores over time. Higher n-3 HUFA:n-6 HUFA ratios were associated with slower increases in somatic complaints in men, whereas among women, higher n-3 HUFA:n-6 PUFA and n-3 PUFA:n-6 PUFA ratios were both linked to putative longitudinal improvement in positive affect over time. Among US adults, n-3:n-6 dietary fatty acid ratio was associated with longitudinal changes in depressive symptoms, with a higher ratio linked to a slower increase in depressive symptoms over time, particularly among women.
Keywords: adults; depressive symptoms; diet; longitudinal studies; n-3 fatty acids.
Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.