Fish and n-3 polyunsaturated fatty acid intake and depressive symptoms: Ryukyus Child Health Study.

BACKGROUND: Epidemiologic evidence on the role of fish and long-chain n-3 polyunsaturated fatty acid intake on depression during adolescence is sparse.

OBJECTIVE: We examined the association between fish, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) intake and depressive symptoms in a group of adolescents.

SUBJECTS AND METHOD: This cross-sectional study, conducted in all public junior high schools in Naha City and Nago City, Okinawa, Japan, included 3067 boys and 3450 girls aged 12 to 15 years (52.3% of the eligible sample). Dietary intake was assessed by using a validated, self-administered diet-history questionnaire. Depressive symptoms were defined as present when participants had a Center for Epidemiologic Studies Depression scale score of >or=16.

RESULTS: The prevalence of depressive symptoms was 22.5% for boys and 31.2% for girls. For boys, fish intake was inversely associated with depressive symptoms (adjusted odds ratio [OR] for depressive symptoms in the highest [compared with the lowest] quintile of intake: 0.73 [95% confidence interval (CI): 0.55-0.97]; P for trend=.04). EPA intake showed an inverse association with depressive symptoms (OR: 0.71 [95% CI: 0.54-0.94]; P=.04). DHA intake also showed a similar inverse, albeit nonsignificant, association (OR: 0.79 [95% CI: 0.59-1.05]; P=.11). In addition, intake of EPA plus DHA was inversely associated with depressive symptoms (OR: 0.72 [95% CI: 0.55-0.96]; P=.08). Conversely, no such associations were observed among girls.

CONCLUSIONS: Higher intake of fish, EPA, and DHA was independently associated with a lower prevalence of depressive symptoms in early male, but not female, adolescents.